diff --git a/cpp/ql/src/semmle/code/cpp/UserType.qll b/cpp/ql/src/semmle/code/cpp/UserType.qll
index ad65bb21185..cbb7f39adbd 100644
--- a/cpp/ql/src/semmle/code/cpp/UserType.qll
+++ b/cpp/ql/src/semmle/code/cpp/UserType.qll
@@ -97,7 +97,6 @@ class UserType extends Type, Declaration, NameQualifyingElement, AccessHolder, @
  * ```
  * class C;
  * typedef int ti;
- * extern void foo(int);
  * ```
  */
 class TypeDeclarationEntry extends DeclarationEntry, @type_decl {
diff --git a/cpp/ql/src/semmle/code/cpp/exprs/ArithmeticOperation.qll b/cpp/ql/src/semmle/code/cpp/exprs/ArithmeticOperation.qll
index 9822495746f..310c7147d37 100644
--- a/cpp/ql/src/semmle/code/cpp/exprs/ArithmeticOperation.qll
+++ b/cpp/ql/src/semmle/code/cpp/exprs/ArithmeticOperation.qll
@@ -37,7 +37,7 @@ class UnaryPlusExpr extends UnaryArithmeticOperation, @unaryplusexpr {
 
 /**
  * A C/C++ GNU conjugation expression.  It operates on `_Complex` or
- * `__complex_`numbers, and is similar to the C99 `conj`, `conjf` and `conjl`
+ * `__complex__ `numbers, and is similar to the C99 `conj`, `conjf` and `conjl`
  * functions.
  * ```
  * _Complex double a =  ( 1.0, 2.0 );
@@ -55,7 +55,7 @@ class ConjugationExpr extends UnaryArithmeticOperation, @conjugation {
  *
  * This is the abstract base QL class for increment and decrement operations.
  *
- * Note that this doesn't include calls to _user-defined_ `operator++`
+ * Note that this does not include calls to _user-defined_ `operator++`
  * or `operator--`.
  */
 abstract class CrementOperation extends UnaryArithmeticOperation {
@@ -74,35 +74,35 @@ abstract class CrementOperation extends UnaryArithmeticOperation {
 /**
  * A C/C++ `++` expression (either prefix or postfix).
  *
- * Note that this doesn't include calls to user-defined `operator++`.
+ * Note that this does not include calls to _user-defined_ `operator++`.
  */
 abstract class IncrementOperation extends CrementOperation { }
 
 /**
  * A C/C++ `--` expression (either prefix or postfix).
  *
- * Note that this doesn't include calls to user-defined `operator--`.
+ * Note that this does not include calls to _user-defined_ `operator--`.
  */
 abstract class DecrementOperation extends CrementOperation { }
 
 /**
  * A C/C++ `++` or `--` prefix expression.
  *
- * Note that this doesn't include calls to user-defined operators.
+ * Note that this does not include calls to _user-defined_ operators.
  */
 abstract class PrefixCrementOperation extends CrementOperation { }
 
 /**
  * A C/C++ `++` or `--` postfix expression.
  *
- * Note that this doesn't include calls to user-defined operators.
+ * Note that this does not include calls to _user-defined_ operators.
  */
 abstract class PostfixCrementOperation extends CrementOperation { }
 
 /**
  * A C/C++ prefix increment expression, as in `++x`.
  *
- * Note that this doesn't include calls to _user-defined_ `operator++`.
+ * Note that this does not include calls to _user-defined_ `operator++`.
  * ```
  * b = ++a;
  * ```
@@ -118,7 +118,7 @@ class PrefixIncrExpr extends IncrementOperation, PrefixCrementOperation, @preinc
 /**
  * A C/C++ prefix decrement expression, as in `--x`.
  *
- * Note that this doesn't include calls to _user-defined_ `operator--`.
+ * Note that this does not include calls to _user-defined_ `operator--`.
  * ```
  * b = --a;
  * ```
@@ -134,7 +134,7 @@ class PrefixDecrExpr extends DecrementOperation, PrefixCrementOperation, @predec
 /**
  * A C/C++ postfix increment expression, as in `x++`.
  *
- * Note that this doesn't include calls to _user-defined_ `operator++`.
+ * Note that this does not include calls to _user-defined_ `operator++`.
  * ```
  * b = a++;
  * ```
@@ -152,7 +152,7 @@ class PostfixIncrExpr extends IncrementOperation, PostfixCrementOperation, @post
 /**
  * A C/C++ postfix decrement expression, as in `x--`.
  *
- * Note that this doesn't include calls to _user-defined_ `operator--`.
+ * Note that this does not include calls to _user-defined_ `operator--`.
  * ```
  * b = a--;
  * ```
diff --git a/cpp/ql/src/semmle/code/cpp/exprs/Assignment.qll b/cpp/ql/src/semmle/code/cpp/exprs/Assignment.qll
index 7690fd7b620..06f9c4de5b0 100644
--- a/cpp/ql/src/semmle/code/cpp/exprs/Assignment.qll
+++ b/cpp/ql/src/semmle/code/cpp/exprs/Assignment.qll
@@ -4,12 +4,14 @@ import semmle.code.cpp.exprs.BitwiseOperation
 
 /**
  * A non-overloaded binary assignment operation, including `=`, `+=`, `&=`,
- * etc. A C++ overloaded operation looks syntactically identical but is instead
+ * etc. A C++ overloaded `operator` looks syntactically identical but is instead
  * a `FunctionCall`.
+ *
+ * This is an abstract root QL class for all (non-overloaded) assignments.
  */
 abstract class Assignment extends Operation {
-  /** Gets the lvalue of this assignment. */
-  Expr getLValue() { this.hasChild(result, 0) }
+  /** Gets the *lvalue* of this assignment. */
+  Expr get*lvalue*() { this.hasChild(result, 0) }
 
   /** Gets the rvalue of this assignment. */
   Expr getRValue() { this.hasChild(result, 1) }
@@ -20,7 +22,7 @@ abstract class Assignment extends Operation {
     this.getRValue().mayBeGloballyImpure()
     or
     not exists(VariableAccess va, LocalScopeVariable v |
-      va = this.getLValue() and
+      va = this.get*lvalue*() and
       v = va.getTarget() and
       not va.getConversion+() instanceof ReferenceDereferenceExpr and
       not v.isStatic()
@@ -51,13 +53,13 @@ abstract class AssignOperation extends Assignment {
 }
 
 /**
- * A non-overloaded arithmetic assignment operation on a non-pointer lvalue:
+ * A non-overloaded arithmetic assignment operation on a non-pointer *lvalue*:
  * `+=`, `-=`, `*=`, `/=` and `%=`.
  */
 abstract class AssignArithmeticOperation extends AssignOperation { }
 
 /**
- * A non-overloaded `+=` assignment expression on a non-pointer lvalue.
+ * A non-overloaded `+=` assignment expression on a non-pointer *lvalue*.
  * ```
  * a += b;
  * ```
@@ -69,7 +71,7 @@ class AssignAddExpr extends AssignArithmeticOperation, @assignaddexpr {
 }
 
 /**
- * A non-overloaded `-=` assignment expression on a non-pointer lvalue.
+ * A non-overloaded `-=` assignment expression on a non-pointer *lvalue*.
  * ```
  * a -= b;
  * ```
@@ -207,11 +209,16 @@ class AssignPointerSubExpr extends AssignOperation, @assignpsubexpr {
 }
 
 /**
- * A C++ variable declaration in an expression where a condition is expected.
- * For example, on the `ConditionDeclExpr` in `if (bool c = x < y)`,
- * `getVariableAccess()` is an access to `c` (with possible casts),
- * `getVariable()` is the variable `c` (which has an initializer `x < y`), and
- * `getInitializingExpr()` is `x < y`.
+ * A C++ variable declaration inside the conditional expression of a `while` or `if`
+ * compound statement.  Declaring a variable this way narrows its lifetime and scope
+ * to be strictly the compound statement itself.  For example:
+ * ```
+ * extern int x, y;
+ * if (bool c = x < y) { do_something_with(c); }
+ * // c is no longer in scope
+ * while (int d = x - y) { do_something_else_with(d); }
+ * // d is no longer is scope
+ * ``` 
  */
 class ConditionDeclExpr extends Expr, @condition_decl {
   /**
diff --git a/cpp/ql/src/semmle/code/cpp/exprs/BuiltInOperations.qll b/cpp/ql/src/semmle/code/cpp/exprs/BuiltInOperations.qll
index 59ee8656106..de178b32ca8 100644
--- a/cpp/ql/src/semmle/code/cpp/exprs/BuiltInOperations.qll
+++ b/cpp/ql/src/semmle/code/cpp/exprs/BuiltInOperations.qll
@@ -2,18 +2,18 @@ import semmle.code.cpp.exprs.Expr
 
 /**
  * A C/C++ builtin operation. This is the root QL class encompassing
- * built-in functionality.
+ * built-in operationality.
  */
 abstract class BuiltInOperation extends Expr {
   override string getCanonicalQLClass() { result = "BuiltInOperation" }
 }
 
 /**
- * A C/C++ `__builtin_va_start` built-in function (used by some
+ * A C/C++ `__builtin_va_start` built-in operation (used by some
  * implementations of `va_start`).
  * ```
-__builtin_va_list ap;
-__builtin_va_start(ap, last_named_param);
+ * __builtin_va_list ap;
+ * __builtin_va_start(ap, last_named_param);
  * ```
  */
 class BuiltInVarArgsStart extends BuiltInOperation, @vastartexpr {
@@ -23,13 +23,13 @@ class BuiltInVarArgsStart extends BuiltInOperation, @vastartexpr {
 }
 
 /**
- * A C/C++ `__builtin_va_end` built-in function (used by some implementations
+ * A C/C++ `__builtin_va_end` built-in operation (used by some implementations
  * of `va_end`).
  * ```
  * __builtin_va_start(ap, last_named_param);
  * ap = __builtin_va_arg(ap, long);
  * __builtin_va_end(ap);
- ```
+ * ```
  */
 class BuiltInVarArgsEnd extends BuiltInOperation, @vaendexpr {
   override string toString() { result = "__builtin_va_end" }
@@ -38,7 +38,7 @@ class BuiltInVarArgsEnd extends BuiltInOperation, @vaendexpr {
 }
 
 /**
- * A C/C++ `__builtin_va_arg` built-in function (used by some implementations
+ * A C/C++ `__builtin_va_arg` built-in operation (used by some implementations
  * of `va_arg`).
  * ```
  * ap = __builtin_va_arg(ap, long);
@@ -51,7 +51,7 @@ class BuiltInVarArg extends BuiltInOperation, @vaargexpr {
 }
 
 /**
- * A C/C++ `__builtin_va_copy` built-in function (used by some implementations
+ * A C/C++ `__builtin_va_copy` built-in operation (used by some implementations
  * of `va_copy`).
  * ```
  * va_list ap, aq;
@@ -78,7 +78,7 @@ class BuiltInNoOp extends BuiltInOperation, @noopexpr {
 }
 
 /**
- * A C++ `__offsetof` built-in function (used by some implementations
+ * A C++ `__offsetof` built-in operation (used by some implementations
  * of `offsetof` in the presence of user-defined `operator &`).
  *
  * It computes the offset (in bytes) of data member `m` from the beginning
@@ -110,7 +110,7 @@ class BuiltInIntAddr extends BuiltInOperation, @intaddrexpr {
 }
 
 /**
- * A C++ `__has_assign` built-in function (used by some implementations of
+ * A C++ `__has_assign` built-in operation (used by some implementations of
  * the `<type_traits>` header).
  *
  * Returns `true` if the type has a copy assignment operator.
@@ -125,7 +125,7 @@ class BuiltInOperationHasAssign extends BuiltInOperation, @hasassignexpr {
 }
 
 /**
- * A C++ `__has_copy` built-in function (used by some implementations of the
+ * A C++ `__has_copy` built-in operation (used by some implementations of the
  * `<type_traits>` header).
  *
  * Returns `true` if the type has a copy constructor.
@@ -140,7 +140,7 @@ class BuiltInOperationHasCopy extends BuiltInOperation, @hascopyexpr {
 }
 
 /**
- * A C++ `__has_nothrow_assign` built-in function (used by some
+ * A C++ `__has_nothrow_assign` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if a copy assignment operator has an empty exception
@@ -156,7 +156,7 @@ class BuiltInOperationHasNoThrowAssign extends BuiltInOperation, @hasnothrowassi
 }
 
 /**
- * A C++ `__has_nothrow_constructor` built-in function (used by some
+ * A C++ `__has_nothrow_constructor` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the default constructor has an empty exception
@@ -172,7 +172,7 @@ class BuiltInOperationHasNoThrowConstructor extends BuiltInOperation, @hasnothro
 }
 
 /**
- * A C++ `__has_nothrow_copy` built-in function (used by some implementations
+ * A C++ `__has_nothrow_copy` built-in operation (used by some implementations
  * of the `<type_traits>` header).
  *
  * Returns `true` if the copy constructor has an empty exception specification.
@@ -187,7 +187,7 @@ class BuiltInOperationHasNoThrowCopy extends BuiltInOperation, @hasnothrowcopy {
 }
 
 /**
- * A C++ `__has_trivial_assign` built-in function (used by some implementations
+ * A C++ `__has_trivial_assign` built-in operation (used by some implementations
  * of the `<type_traits>` header).
  *
  * Returns `true` if the type has a trivial (compiler-generated) assignment
@@ -203,7 +203,7 @@ class BuiltInOperationHasTrivialAssign extends BuiltInOperation, @hastrivialassi
 }
 
 /**
- * A C++ `__has_trivial_constructor` built-in function (used by some
+ * A C++ `__has_trivial_constructor` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the type has a trivial (compiler-generated) constructor.
@@ -218,7 +218,7 @@ class BuiltInOperationHasTrivialConstructor extends BuiltInOperation, @hastrivia
 }
 
 /**
- * A C++ `__has_trivial_copy` built-in function (used by some implementations
+ * A C++ `__has_trivial_copy` built-in operation (used by some implementations
  * of the `<type_traits>` header).
  *
  * Returns true if the type has a trivial (compiler-generated) copy constructor.
@@ -233,7 +233,7 @@ class BuiltInOperationHasTrivialCopy extends BuiltInOperation, @hastrivialcopy {
 }
 
 /**
- * A C++ `__has_trivial_destructor` built-in function (used by some
+ * A C++ `__has_trivial_destructor` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the type has a trivial (compiler-generated) destructor.
@@ -248,7 +248,7 @@ class BuiltInOperationHasTrivialDestructor extends BuiltInOperation, @hastrivial
 }
 
 /**
- * A C++ `__has_user_destructor` built-in function (used by some
+ * A C++ `__has_user_destructor` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns true if the type has a user-declared destructor.
@@ -263,7 +263,7 @@ class BuiltInOperationHasUserDestructor extends BuiltInOperation, @hasuserdestr
 }
 
 /**
- * A C++ `__has_virtual_destructor` built-in function (used by some
+ * A C++ `__has_virtual_destructor` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the type has a virtual destructor.
@@ -281,7 +281,7 @@ class BuiltInOperationHasVirtualDestructor extends BuiltInOperation, @hasvirtual
 }
 
 /**
- * A C++ `__is_abstract` built-in function (used by some implementations of the
+ * A C++ `__is_abstract` built-in operation (used by some implementations of the
  * `<type_traits>` header).
  *
  * Returns `true` if the class has at least one pure virtual function.
@@ -296,7 +296,7 @@ class BuiltInOperationIsAbstract extends BuiltInOperation, @isabstractexpr {
 }
 
 /**
- * A C++ `__is_base_of` built-in function (used by some implementations of the
+ * A C++ `__is_base_of` built-in operation (used by some implementations of the
  * `<type_traits>` header).
  *
  * Returns `true` if the first type is a base class of the second type, of if both types are the same.
@@ -311,7 +311,7 @@ class BuiltInOperationIsBaseOf extends BuiltInOperation, @isbaseofexpr {
 }
 
 /**
- * A C++ `__is_class` built-in function (used by some implementations of the
+ * A C++ `__is_class` built-in operation (used by some implementations of the
  * `<type_traits>` header).
  *
  * Returns `true` if the type is a `class` or a `struct`.
@@ -326,7 +326,7 @@ class BuiltInOperationIsClass extends BuiltInOperation, @isclassexpr {
 }
 
 /**
- * A C++ `__is_convertible_to` built-in function (used by some implementations
+ * A C++ `__is_convertible_to` built-in operation (used by some implementations
  * of the `<type_traits>` header).
  *
  * Returns `true` if the first type can be converted to the second type.
@@ -341,7 +341,7 @@ class BuiltInOperationIsConvertibleTo extends BuiltInOperation, @isconvtoexpr {
 }
 
 /**
- * A C++ `__is_empty` built-in function (used by some implementations of the
+ * A C++ `__is_empty` built-in operation (used by some implementations of the
  * `<type_traits>` header).
  *
  * Returns `true` if the type has no instance data members.
@@ -356,7 +356,7 @@ class BuiltInOperationIsEmpty extends BuiltInOperation, @isemptyexpr {
 }
 
 /**
- * A C++ `__is_enum` built-in function (used by some implementations of the
+ * A C++ `__is_enum` built-in operation (used by some implementations of the
  * `<type_traits>` header).
  *
  * Returns true if the type is an `enum`.
@@ -371,12 +371,12 @@ class BuiltInOperationIsEnum extends BuiltInOperation, @isenumexpr {
 }
 
 /**
- * A C++ `__is_pod` built-in function (used by some implementations of the
+ * A C++ `__is_pod` built-in operation (used by some implementations of the
  * `<type_traits>` header).
  *
  * Returns `true` if the type is a `class`, `struct` or `union`,  WITHOUT
  * (1) constructors, (2) private or protected non-static members, (3) base
-*  classes, or (4) virtual functions.
+ *  classes, or (4) virtual functions.
  * ```
  * bool v = __is_pod(MyType);
  * ```
@@ -388,7 +388,7 @@ class BuiltInOperationIsPod extends BuiltInOperation, @ispodexpr {
 }
 
 /**
- * A C++ `__is_polymorphic` built-in function (used by some implementations
+ * A C++ `__is_polymorphic` built-in operation (used by some implementations
  * of the `<type_traits>` header).
  *
  * Returns `true` if the type has at least one virtual function.
@@ -403,7 +403,7 @@ class BuiltInOperationIsPolymorphic extends BuiltInOperation, @ispolyexpr {
 }
 
 /**
- * A C++ `__is_union` built-in function (used by some implementations of the
+ * A C++ `__is_union` built-in operation (used by some implementations of the
  * `<type_traits>` header).
  *
  * Returns `true` if the type is a `union`.
@@ -423,7 +423,7 @@ class BuiltInOperationIsUnion extends BuiltInOperation, @isunionexpr {
 deprecated class BuiltInOperationBuiltInTypes = BuiltInOperationBuiltInTypesCompatibleP;
 
 /**
- * A C++ `__builtin_types_compatible_p` built-in function (used by some
+ * A C++ `__builtin_types_compatible_p` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the two types are the same (modulo qualifiers).
@@ -501,7 +501,7 @@ class BuiltInOperationBuiltInAddressOf extends UnaryOperation, BuiltInOperation,
 }
 
 /**
- * The `__is_trivially_constructible` built-in function (used by some
+ * The `__is_trivially_constructible` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the type has a trivial (compiler-generated) default
@@ -521,7 +521,7 @@ class BuiltInOperationIsTriviallyConstructible extends BuiltInOperation,
 }
 
 /**
- * The `__is_destructible` built-in function (used by some implementations
+ * The `__is_destructible` built-in operation (used by some implementations
  * of the `<type_traits>` header).
  *
  * Returns `true` if the type's destructor is not `delete`d and is accessible
@@ -538,7 +538,7 @@ class BuiltInOperationIsDestructible extends BuiltInOperation, @isdestructibleex
 }
 
 /**
- * The `__is_nothrow_destructible` built-in function (used by some
+ * The `__is_nothrow_destructible` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the type is destructible and whose constructor, and those
@@ -555,7 +555,7 @@ class BuiltInOperationIsNothrowDestructible extends BuiltInOperation, @isnothrow
 }
 
 /**
- * The `__is_trivially_destructible` built-in function (used by some
+ * The `__is_trivially_destructible` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the type is destructible and whose constructor, and those
@@ -571,7 +571,7 @@ class BuiltInOperationIsTriviallyDestructible extends BuiltInOperation, @istrivi
 }
 
 /**
- * The `__is_trivially_assignable` built-in function (used by some
+ * The `__is_trivially_assignable` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the assignment operator `C::operator =(const C& c)` is
@@ -591,7 +591,7 @@ class BuiltInOperationIsTriviallyAssignable extends BuiltInOperation, @istrivial
 }
 
 /**
- * The `__is_nothrow_assignable` built-in function (used by some
+ * The `__is_nothrow_assignable` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns true if there exists a `C::operator =(const C& c) nothrow`
@@ -607,7 +607,7 @@ class BuiltInOperationIsNothrowAssignable extends BuiltInOperation, @isnothrowas
 }
 
 /**
- * The `__is_standard_layout` built-in function (used by some implementations
+ * The `__is_standard_layout` built-in operation (used by some implementations
  * of the `<type_traits>` header).
  *
  * Returns `true` if the type is a primitive type, or a `class`, `struct` or
@@ -627,7 +627,7 @@ class BuiltInOperationIsStandardLayout extends BuiltInOperation, @isstandardlayo
 }
 
 /**
- * The `__is_trivially_copyable` built-in function (used by some
+ * The `__is_trivially_copyable` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if instances of this type can be copied by trivial (compiler-
@@ -641,7 +641,7 @@ class BuiltInOperationIsTriviallyCopyable extends BuiltInOperation, @istrivially
 }
 
 /**
- * The `__is_literal_type` built-in function (used by some implementations of
+ * The `__is_literal_type` built-in operation (used by some implementations of
  * the `<type_traits>` header).
  *
  * Returns `true` if the type is a scalar type, a reference type or an array of
@@ -661,7 +661,7 @@ class BuiltInOperationIsLiteralType extends BuiltInOperation, @isliteraltypeexpr
 }
 
 /**
- * The `__has_trivial_move_constructor` built-in function (used by some
+ * The `__has_trivial_move_constructor` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns true if the move (`&&`) constructor can be generated by the
@@ -679,7 +679,7 @@ class BuiltInOperationHasTrivialMoveConstructor extends BuiltInOperation,
 }
 
 /**
- * The `__has_trivial_move_assign` built-in function (used by some
+ * The `__has_trivial_move_assign` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns if the move-assign operator `C::operator =(C &&c)` is trivial
@@ -698,7 +698,7 @@ class BuiltInOperationHasTrivialMoveAssign extends BuiltInOperation, @hastrivial
 }
 
 /**
- * The `__has_nothrow_move_assign` built-in function (used by some
+ * The `__has_nothrow_move_assign` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the type has a `C::operator=(C&& c) nothrow`, that is,
@@ -714,7 +714,7 @@ class BuiltInOperationHasNothrowMoveAssign extends BuiltInOperation, @hasnothrow
 }
 
 /**
- * The `__is_constructible` built-in function (used by some implementations
+ * The `__is_constructible` built-in operation (used by some implementations
  * of the `<type_traits>` header).
  *
  * Returns `true` if the type can be constructed using specified arguments
@@ -733,7 +733,7 @@ class BuiltInOperationIsConstructible extends BuiltInOperation, @isconstructible
 }
 
 /**
- * The `__is_nothrow_constructible` built-in function (used by some
+ * The `__is_nothrow_constructible` built-in operation (used by some
  * implementations of the `<type_traits>` header).
  *
  * Returns `true` if the type is constructable and all its constructors have an
@@ -749,7 +749,7 @@ class BuiltInOperationIsNothrowConstructible extends BuiltInOperation, @isnothro
 }
 
 /**
- * The `__has_finalizer` built-in function.  This is a Microsoft extension.
+ * The `__has_finalizer` built-in operation.  This is a Microsoft extension.
  *
  * Returns `true` if the type defines a _finalizer_ `C::!C(void)`, to be called
  * from either the regular destructor or the garbage collector.
@@ -764,7 +764,7 @@ class BuiltInOperationHasFinalizer extends BuiltInOperation, @hasfinalizerexpr {
 }
 
 /**
- * The `__is_delegate` built-in function.  This is a Microsoft extension.
+ * The `__is_delegate` built-in operation.  This is a Microsoft extension.
  *
  * Returns `true` if the function has been declared as a `delegate`, used in
  * message forwarding.  Please see
@@ -778,7 +778,7 @@ class BuiltInOperationIsDelegate extends BuiltInOperation, @isdelegateexpr {
 }
 
 /**
- * The `__is_interface_class` built-in function.  This is a Microsoft extension.
+ * The `__is_interface_class` built-in operation.  This is a Microsoft extension.
  *
  * Returns `true` if the type has been declared as an `interface`.  Please see
  * https://docs.microsoft.com/en-us/cpp/extensions/interface-class-cpp-component-extensions
@@ -791,7 +791,7 @@ class BuiltInOperationIsInterfaceClass extends BuiltInOperation, @isinterfacecla
 }
 
 /**
- * The `__is_ref_array` built-in function.  This is a Microsoft extension.
+ * The `__is_ref_array` built-in operation.  This is a Microsoft extension.
  *
  * Returns `true` if the object passed in is a _platform array_.  Please see
  * https://docs.microsoft.com/en-us/cpp/extensions/arrays-cpp-component-extensions
@@ -808,7 +808,7 @@ class BuiltInOperationIsRefArray extends BuiltInOperation, @isrefarrayexpr {
 }
 
 /**
- * The `__is_ref_class` built-in function.  This is a Microsoft extension.
+ * The `__is_ref_class` built-in operation.  This is a Microsoft extension.
  *
  * Returns `true` if the type is a _reference class_.  Please see
  * https://docs.microsoft.com/en-us/cpp/extensions/classes-and-structs-cpp-component-extensions
@@ -825,7 +825,7 @@ class BuiltInOperationIsRefClass extends BuiltInOperation, @isrefclassexpr {
 }
 
 /**
- * The `__is_sealed` built-in function.  This is a Microsoft extension.
+ * The `__is_sealed` built-in operation.  This is a Microsoft extension.
  *
  * Returns `true` if a given class or virtual function is marked as `sealed`,
  * meaning that it cannot be extended or overridden.  The `sealed` keyword
@@ -843,7 +843,7 @@ class BuiltInOperationIsSealed extends BuiltInOperation, @issealedexpr {
 }
 
 /**
- * The `__is_simple_value_class` built-in function.  This is a Microsoft extension.
+ * The `__is_simple_value_class` built-in operation.  This is a Microsoft extension.
  *
  * Returns `true` if passed a value type that contains no references to the
  * garbage-collected heap.
@@ -862,7 +862,7 @@ class BuiltInOperationIsSimpleValueClass extends BuiltInOperation, @issimplevalu
 }
 
 /**
- * The `__is_value_class` built-in function.  This is a Microsoft extension.
+ * The `__is_value_class` built-in operation.  This is a Microsoft extension.
  *
  * Returns `true` if passed a value type.  Please see
  * https://docs.microsoft.com/en-us/cpp/extensions/classes-and-structs-cpp-component-extensions
@@ -879,7 +879,7 @@ class BuiltInOperationIsValueClass extends BuiltInOperation, @isvalueclassexpr {
 }
 
 /**
- * The `__is_final` built-in function (used by some implementations of the
+ * The `__is_final` built-in operation (used by some implementations of the
  * `<type_traits>` header).
  *
  * Returns `true` if the `class` has been marked with the `final` specifier.
@@ -913,6 +913,14 @@ class BuiltInChooseExpr extends BuiltInOperation, @builtinchooseexpr {
 
 /**
  * Fill operation on a vector. This is a GNU extension.
+ *
+ * A single scalar value is used to populate all the elements in a vector.
+ * In the example below, the scalar value is `25`:
+ * ```
+ * typedef int v16i __attribute__((vector_size(16)));
+ * v16i src, dst;
+ * dst = src << 25;
+ * ```
  */
 class VectorFillOperation extends UnaryOperation, @vec_fill {
   override string getOperator() { result = "(vector fill)" }
diff --git a/cpp/ql/src/semmle/code/cpp/exprs/Call.qll b/cpp/ql/src/semmle/code/cpp/exprs/Call.qll
index 1ee216ca63c..62db9e29949 100644
--- a/cpp/ql/src/semmle/code/cpp/exprs/Call.qll
+++ b/cpp/ql/src/semmle/code/cpp/exprs/Call.qll
@@ -4,6 +4,8 @@ private import semmle.code.cpp.dataflow.EscapesTree
 
 /**
  * A C/C++ call.
+ *
+ * This is the abstract root QL class for all types of calls.
  */
 abstract class Call extends Expr, NameQualifiableElement {
   /**
@@ -228,7 +230,7 @@ class FunctionCall extends Call, @funbindexpr {
    * Gets the function called by this call.
    *
    * In the case of virtual function calls, the result is the most-specific function in the override tree (as
-   * determined by the compiler) such that the target at runtime will be one of result.getAnOverridingFunction*().
+   * determined by the compiler) such that the target at runtime will be one of **result.getAnOverridingFunction\*()**.
    */
   override Function getTarget() { funbind(underlyingElement(this), unresolveElement(result)) }
 
@@ -273,7 +275,11 @@ class FunctionCall extends Call, @funbindexpr {
 }
 
 /**
- * An instance of unary operator * applied to a user-defined type.
+ * An instance of a _user-defined_ unary `operator*` applied to its argument.
+ * ```
+ * T1 operator*(const T2 &);
+ * T1 a; T2 b;
+ * a = *b;
  */
 class OverloadedPointerDereferenceExpr extends FunctionCall {
   OverloadedPointerDereferenceExpr() {
@@ -281,6 +287,8 @@ class OverloadedPointerDereferenceExpr extends FunctionCall {
     getTarget().getEffectiveNumberOfParameters() = 1
   }
 
+  override string getCanonicalQLClass() { result = "OverloadedPointerDereferenceExpr" }
+
   /**
    * Gets the expression this operator * applies to.
    */
@@ -317,11 +325,18 @@ class OverloadedPointerDereferenceExpr extends FunctionCall {
 }
 
 /**
- * An instance of operator [] applied to a user-defined type.
+ * An instance of a _user-defined_ binary `operator[]` applied to its arguments.
+ * ```
+ * struct T2 { T1 operator[](const T3 &); };
+ * T1 a; T2 b; T3 c;
+ * a = b[c];
+ * ```
  */
 class OverloadedArrayExpr extends FunctionCall {
   OverloadedArrayExpr() { getTarget().hasName("operator[]") }
 
+  override string getCanonicalQLClass() { result = "OverloadedArrayExpr" }
+
   /**
    * Gets the expression being subscripted.
    */
@@ -387,7 +402,7 @@ class VariableCall extends ExprCall {
 /**
  * A call to a constructor.
  * ```
- * struct S { S(void); }
+ * struct S { S(void) {} };
  * S s;
  * ```
  */
@@ -401,7 +416,7 @@ class ConstructorCall extends FunctionCall {
 }
 
 /**
- * A C++ `throw` expression. 
+ * A C++ `throw` expression.
  * ```
  * throw Exc(2);
  * ```
@@ -437,11 +452,8 @@ class ReThrowExpr extends ThrowExpr {
 /**
  * A call to a destructor.
  * ```
- struct S { ~S(void); };
- void foo() {
-  S s;
-  s.~S(); 
- }
+ * struct S { ~S(void) {} } *s;
+ * s->~S();
  * ```
  */
 class DestructorCall extends FunctionCall {
@@ -479,6 +491,9 @@ class VacuousDestructorCall extends Expr, @vacuous_destructor_call {
 /**
  * An initialization of a base class or member variable performed as part
  * of a constructor's explicit initializer list or implicit actions.
+ *
+ * This is a QL root class for reprenting various types of constructor
+ * initializations.
  */
 class ConstructorInit extends Expr, @ctorinit {
   override string getCanonicalQLClass() { result = "ConstructorInit" }
@@ -495,6 +510,15 @@ class ConstructorBaseInit extends ConstructorInit, ConstructorCall {
 /**
  * A call to a constructor of a direct non-virtual base class as part of a
  * constructor's initializer list or compiler-generated actions.
+ * ```
+ * struct S {
+ *   int a;
+ *   S(int b): a(b) {}
+ * };
+ * struct T: S {
+ *   T(): S(33) {}  // S(33) is a constructor call
+ * };
+ * ```
  */
 class ConstructorDirectInit extends ConstructorBaseInit, @ctordirectinit {
   override string getCanonicalQLClass() { result = "ConstructorDirectInit" }
@@ -506,6 +530,15 @@ class ConstructorDirectInit extends ConstructorBaseInit, @ctordirectinit {
  *
  * If the virtual base class has already been initialized, then this
  * call won't be performed.
+ * ```
+ * struct S {
+ *   int a;
+ *   S(int b): a(b) {}
+ * };
+ * struct T: virtual S {
+ *   T(): S(33) {}  // S(33) is a call to a virtual base constructor
+ * };
+ * ```
  */
 class ConstructorVirtualInit extends ConstructorBaseInit, @ctorvirtualinit {
   override string getCanonicalQLClass() { result = "ConstructorVirtualInit" }
@@ -514,6 +547,13 @@ class ConstructorVirtualInit extends ConstructorBaseInit, @ctorvirtualinit {
 /**
  * A call to a constructor of the same class as part of a constructor's
  * initializer list, which delegates object construction (C++11 only).
+ * ```
+ * struct S {
+ *  int a;
+ *  S(int b): a(b) { }
+ *  S(): S(0) { } // delegation to another constructor
+ * };
+ * ```
  */
 class ConstructorDelegationInit extends ConstructorBaseInit, @ctordelegatinginit {
   override string getCanonicalQLClass() { result = "ConstructorDelegationInit" }
@@ -522,6 +562,14 @@ class ConstructorDelegationInit extends ConstructorBaseInit, @ctordelegatinginit
 /**
  * An initialization of a member variable performed as part of a
  * constructor's explicit initializer list or implicit actions.
+ * In the example below, member variable `b` is being initialized by
+ * constructor parameter `a`:
+ * ```
+ * struct S {
+ *   int b;
+ *   S(int a): b(a) {}
+ * } s(2);
+ * ```
  */
 class ConstructorFieldInit extends ConstructorInit, @ctorfieldinit {
   /** Gets the field being initialized. */
@@ -563,6 +611,12 @@ class DestructorBaseDestruction extends DestructorCall, DestructorDestruction {
 /**
  * A call to a destructor of a direct non-virtual base class as part of a
  * destructor's compiler-generated actions.
+ * ```
+ * struct S {  ~S(void) {} };
+ * struct T: S {
+ *   ~T(void) {} // will call ~S()
+ * };
+ * ```
  */
 class DestructorDirectDestruction extends DestructorBaseDestruction, @dtordirectdestruct {
   override string getCanonicalQLClass() { result = "DestructorDirectDestruction" }
@@ -574,6 +628,12 @@ class DestructorDirectDestruction extends DestructorBaseDestruction, @dtordirect
  *
  * If the virtual base class wasn't initialized by the ConstructorVirtualInit
  * in the corresponding constructor, then this call won't be performed.
+ * ```
+ * struct S {  ~S(void) {} };
+ * struct T: virtual S {
+ *   ~T(void) {} // will call ~S()
+ * };
+ * ```
  */
 class DestructorVirtualDestruction extends DestructorBaseDestruction, @dtorvirtualdestruct {
   override string getCanonicalQLClass() { result = "DestructorVirtualDestruction" }
@@ -582,6 +642,13 @@ class DestructorVirtualDestruction extends DestructorBaseDestruction, @dtorvirtu
 /**
  * A destruction of a member variable performed as part of a
  * destructor's compiler-generated actions.
+ * ```
+ * struct S {  ~S(void) {} };
+ * struct T {
+ *   S s;
+ *   ~T(void) {}  // will call s.~S()
+ * };
+ * ```
  */
 class DestructorFieldDestruction extends DestructorDestruction, @dtorfielddestruct {
   /** Gets the field being destructed. */
diff --git a/cpp/ql/src/semmle/code/cpp/exprs/Cast.qll b/cpp/ql/src/semmle/code/cpp/exprs/Cast.qll
index df34515bd46..1c16889b23d 100644
--- a/cpp/ql/src/semmle/code/cpp/exprs/Cast.qll
+++ b/cpp/ql/src/semmle/code/cpp/exprs/Cast.qll
@@ -22,17 +22,20 @@ abstract class Conversion extends Expr {
 /**
  * A C/C++ cast expression.
  *
- * To get the type which the expression is being cast to, use getType().
+ * To get the type which the expression is being cast to, use **Cast::getType()**.
  *
- * There are two groups of subtypes of `Cast`. The first group differentiates
- * between the different cast syntax forms, e.g. `CStyleCast`, `StaticCast`,
+ * There are two groups of subtypes of **Cast**. The first group differentiates
+ * between the different cast syntax forms, e.g. **CStyleCast**, **StaticCast**,
  * etc. The second group differentiates between the semantic operation being
- * performed by the cast, e.g. `IntegralConversion`, `PointerBaseClassConversion`,
+ * performed by the cast, e.g. **IntegralConversion**, **PointerBaseClassConversion**,
  * etc.
  * The two groups are largely orthogonal to one another. For example, a
- * cast that is syntactically as `CStyleCast` may also be an `IntegralConversion`,
- * a `PointerBaseClassConversion`, or some other semantic conversion. Similarly,
- * a `PointerDerivedClassConversion` may also be a `CStyleCast` or a `StaticCast`.
+ * cast that is syntactically as **CStyleCast** may also be an **IntegralConversion**,
+ * a **PointerBaseClassConversion**, or some other semantic conversion. Similarly,
+ * a **PointerDerivedClassConversion** may also be a **CStyleCast** or a **StaticCast**.
+ *
+ * This is an abstract root QL class representing the different casts.  For
+ * specific examples, consult the documentation for any of QL classes mentioned above.
  */
 abstract class Cast extends Conversion, @cast {
   /**
@@ -44,7 +47,7 @@ abstract class Cast extends Conversion, @cast {
 
 /**
  * INTERNAL: Do not use.
- * Query predicates used to check invariants that should hold for all `Cast`
+ * Query predicates used to check invariants that should hold for all **Cast**
  * nodes. To run all sanity queries for the ASTs, including the ones below,
  * run "semmle/code/cpp/ASTSanity.ql".
  */
@@ -71,6 +74,10 @@ module CastSanity {
 
 /**
  * A cast expression in C, or a C-style cast expression in C++.
+ * ```
+ * float f = 3.0f;
+ * int i = (int)f;
+ * ```
  */
 class CStyleCast extends Cast, @c_style_cast {
   override string toString() { result = "(" + this.getType().getName() + ")..." }
@@ -82,6 +89,14 @@ class CStyleCast extends Cast, @c_style_cast {
 
 /**
  * A C++ `static_cast` expression.
+ *
+ * Please see https://en.cppreference.com/w/cpp/language/static_cast for
+ * more information.
+ * ```
+ * struct T: S {};
+ * struct S *s = get_S();
+ * struct T *t = static_cast<struct T *>(s); // downcast
+ * ```
  */
 class StaticCast extends Cast, @static_cast {
   override string toString() { result = "static_cast<" + this.getType().getName() + ">..." }
@@ -93,6 +108,13 @@ class StaticCast extends Cast, @static_cast {
 
 /**
  * A C++ `const_cast` expression.
+ *
+ * Please see https://en.cppreference.com/w/cpp/language/const_cast for
+ * more information.
+ * ```
+ * const struct S *s = get_S();
+ * struct S *t = const_cast<struct S *>(s);
+ * ```
  */
 class ConstCast extends Cast, @const_cast {
   override string toString() { result = "const_cast<" + this.getType().getName() + ">..." }
@@ -104,6 +126,13 @@ class ConstCast extends Cast, @const_cast {
 
 /**
  * A C++ `reinterpret_cast` expression.
+ *
+ * Please see https://en.cppreference.com/w/cpp/language/reinterpret_cast for
+ * more information.
+ * ```
+ * struct S *s = get_S();
+ * std::uintptr_t p = reinterpret_cast<std::uintptr_t>(s);
+ * ```
  */
 class ReinterpretCast extends Cast, @reinterpret_cast {
   override string toString() { result = "reinterpret_cast<" + this.getType().getName() + ">..." }
@@ -135,7 +164,11 @@ private predicate isPointerToMemberOrNullPointer(Type type) {
 }
 
 /**
- * A conversion from one arithmetic or enum type to another.
+ * A conversion from one arithmetic or `enum` type to another.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class ArithmeticConversion extends Cast {
   ArithmeticConversion() {
@@ -149,6 +182,10 @@ class ArithmeticConversion extends Cast {
 
 /**
  * A conversion from one integral or enum type to another.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class IntegralConversion extends ArithmeticConversion {
   IntegralConversion() {
@@ -164,7 +201,11 @@ class IntegralConversion extends ArithmeticConversion {
 }
 
 /**
- * A conversion from one floating point type to another.
+ * A conversion from one floating point type.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class FloatingPointConversion extends ArithmeticConversion {
   FloatingPointConversion() {
@@ -181,6 +222,10 @@ class FloatingPointConversion extends ArithmeticConversion {
 
 /**
  * A conversion from a floating point type to an integral or enum type.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class FloatingPointToIntegralConversion extends ArithmeticConversion {
   FloatingPointToIntegralConversion() {
@@ -197,6 +242,10 @@ class FloatingPointToIntegralConversion extends ArithmeticConversion {
 
 /**
  * A conversion from an integral or enum type to a floating point type.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class IntegralToFloatingPointConversion extends ArithmeticConversion {
   IntegralToFloatingPointConversion() {
@@ -212,10 +261,16 @@ class IntegralToFloatingPointConversion extends ArithmeticConversion {
 }
 
 /**
- * A conversion from one pointer type to another. The conversion does
+ * A conversion from one pointer type to another.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
+ *
+ * The conversion does
  * not modify the value of the pointer. For pointer conversions involving
- * casts between base and derived classes, see `BaseClassConversion` and
- * `DerivedClassConversion`.
+ * casts between base and derived classes, please see see **BaseClassConversion** or
+ * **DerivedClassConversion**.
  */
 class PointerConversion extends Cast {
   PointerConversion() {
@@ -232,10 +287,16 @@ class PointerConversion extends Cast {
 }
 
 /**
- * A conversion from one pointer-to-member type to another. The conversion
- * does not modify the value of the pointer-to-member. For pointer-to-member
- * conversions involving casts between base and derived classes, see
- * `PointerToMemberBaseClassConversion` and `PointerToMemberDerivedClassConversion`.
+ * A conversion from one pointer-to-member type to another.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
+ *
+ * The conversion does not modify the value of the pointer-to-member.
+ * For pointer-to-member conversions involving casts between base and
+ * derived classes, please see **PointerToMemberBaseClassConversion**
+ * or **PointerToMemberDerivedClassConversion**.
  */
 class PointerToMemberConversion extends Cast {
   PointerToMemberConversion() {
@@ -263,6 +324,10 @@ class PointerToMemberConversion extends Cast {
 
 /**
  * A conversion from a pointer type to an integral or enum type.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class PointerToIntegralConversion extends Cast {
   PointerToIntegralConversion() {
@@ -280,6 +345,10 @@ class PointerToIntegralConversion extends Cast {
 
 /**
  * A conversion from an integral or enum type to a pointer type.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class IntegralToPointerConversion extends Cast {
   IntegralToPointerConversion() {
@@ -297,7 +366,11 @@ class IntegralToPointerConversion extends Cast {
 
 /**
  * A conversion to `bool`. Returns `false` if the source value is zero,
- * false, or nullptr. Returns `true` otherwise.
+ * `false`, or `nullptr`. Returns `true` otherwise.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class BoolConversion extends Cast {
   BoolConversion() { conversionkinds(underlyingElement(this), 1) }
@@ -309,6 +382,10 @@ class BoolConversion extends Cast {
 
 /**
  * A conversion to `void`.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class VoidConversion extends Cast {
   VoidConversion() {
@@ -322,11 +399,16 @@ class VoidConversion extends Cast {
 }
 
 /**
- * A conversion between two pointers or glvalues related by inheritance. The
- * base class will always be either a direct base class of the derived class,
+ * A conversion between two pointers or *glvalue*s related by inheritance.
+ *
+ * The base class will always be either a direct base class of the derived class,
  * or a virtual base class of the derived class. A conversion to an indirect
  * non-virtual base class will be represented as a sequence of conversions to
  * direct base classes.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class InheritanceConversion extends Cast {
   InheritanceConversion() {
@@ -377,8 +459,12 @@ private Class getConversionClass(Expr expr) {
 }
 
 /**
- * A conversion from a pointer or glvalue of a derived class to a pointer or
- * glvalue of a direct or virtual base class.
+ * A conversion from a pointer or *glvalue* of a derived class to a pointer or
+ * *glvalue* of a direct or virtual base class.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class BaseClassConversion extends InheritanceConversion {
   BaseClassConversion() { conversionkinds(underlyingElement(this), 2) }
@@ -400,8 +486,12 @@ class BaseClassConversion extends InheritanceConversion {
 }
 
 /**
- * A conversion from a pointer or glvalue to a base class to a pointer or glvalue
+ * A conversion from a pointer or *glvalue* to a base class to a pointer or *glvalue*
  * to a direct derived class.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class DerivedClassConversion extends InheritanceConversion {
   DerivedClassConversion() { conversionkinds(underlyingElement(this), 3) }
@@ -420,6 +510,10 @@ class DerivedClassConversion extends InheritanceConversion {
 /**
  * A conversion from a pointer-to-member of a derived class to a pointer-to-member
  * of an immediate base class.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class PointerToMemberBaseClassConversion extends Cast {
   PointerToMemberBaseClassConversion() { conversionkinds(underlyingElement(this), 4) }
@@ -436,6 +530,10 @@ class PointerToMemberBaseClassConversion extends Cast {
 /**
  * A conversion from a pointer-to-member of a base class to a pointer-to-member
  * of an immediate derived class.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class PointerToMemberDerivedClassConversion extends Cast {
   PointerToMemberDerivedClassConversion() { conversionkinds(underlyingElement(this), 5) }
@@ -450,9 +548,13 @@ class PointerToMemberDerivedClassConversion extends Cast {
 }
 
 /**
- * A conversion of a glvalue from one type to another. The conversion does not
- * modify the address of the glvalue. For glvalue conversions involving base and
+ * A conversion of a *glvalue* from one type to another. The conversion does not
+ * modify the address of the *glvalue*. For *glvalue* conversions involving base and
  * derived classes, see `BaseClassConversion` and `DerivedClassConversion`.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class GlvalueConversion extends Cast {
   GlvalueConversion() { conversionkinds(underlyingElement(this), 6) }
@@ -465,18 +567,22 @@ class GlvalueConversion extends Cast {
 }
 
 /**
- * The adjustment of the type of a class prvalue. Most commonly seen in code
+ * The adjustment of the type of a class *prvalue*. Most commonly seen in code
  * similar to:
- *
+ * ```
  * class String { ... };
  * String func();
  * void caller() {
  *   const String& r = func();
  * }
- *
- * In the above example, the result of the call to `func` is a prvalue of type
+ * ```
+ * In the above example, the result of the call to `func` is a *prvalue* of type
  * `String`, which will be adjusted to type `const String` before being bound
  * to the reference.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class PrvalueAdjustmentConversion extends Cast {
   PrvalueAdjustmentConversion() { conversionkinds(underlyingElement(this), 7) }
@@ -490,6 +596,14 @@ class PrvalueAdjustmentConversion extends Cast {
 
 /**
  * A C++ `dynamic_cast` expression.
+ *
+ * Please see https://en.cppreference.com/w/cpp/language/dynamic_cast for
+ * more information.
+ * ```
+ * struct T: S {};
+ * struct S *s = get_S();
+ * struct T *t = dynamic_cast<struct T *>(s); // downcast
+ * ```
  */
 class DynamicCast extends Cast, @dynamic_cast {
   override string toString() { result = "dynamic_cast<" + this.getType().getName() + ">..." }
@@ -504,6 +618,11 @@ class DynamicCast extends Cast, @dynamic_cast {
 /**
  * A Microsoft C/C++ `__uuidof` expression that returns the UUID of a type, as
  * specified by the `__declspec(uuid)` attribute.
+ * ```
+ * struct UUID { char a[16]; };
+ * struct __declspec(uuid("{01234567-89ab-cdef-0123-456789ABCDEF}")) S {};
+ * UUID uuid = __uuidof(S);
+ * ```
  */
 class UuidofOperator extends Expr, @uuidof {
   override string toString() {
@@ -519,22 +638,18 @@ class UuidofOperator extends Expr, @uuidof {
 }
 
 /**
- * A C++ `typeid` expression which provides runtime type information
- * about an expression or type.
+ * A C++ `typeid` expression which provides run-time type information (RTTI)
+ * about its argument.
+ *
+ * Please see https://en.cppreference.com/w/cpp/language/typeid for more
+ * information.
+ * ```
+ * Base *ptr = new Derived;
+ * const std::type_info &info1 = typeid(ptr);
+ * printf("the type of ptr is: %s\n", typeid(ptr).name);
+ * ```
  */
 class TypeidOperator extends Expr, @type_id {
-  /**
-   * Gets the type that is returned by this typeid expression.
-   *
-   * For example in the following code the `typeid` returns the
-   * type `MyClass *`.
-   *
-   * ```
-   * MyClass *ptr;
-   *
-   * printf("the type of ptr is: %s\n", typeid(ptr).name);
-   * ```
-   */
   Type getResultType() { typeid_bind(underlyingElement(this), unresolveElement(result)) }
 
   /**
@@ -566,6 +681,10 @@ class TypeidOperator extends Expr, @type_id {
  *
  * This expression only appears in templates themselves - in any actual
  * instantiations, "sizeof...(x)" will be replaced by its integer value.
+ * ```
+ * template < typename... T >
+ * int count ( T &&... t ) { return sizeof... ( t ); }
+ * ```
  */
 class SizeofPackOperator extends Expr, @sizeof_pack {
   override string toString() { result = "sizeof...(...)" }
@@ -586,6 +705,9 @@ abstract class SizeofOperator extends Expr, @runtime_sizeof {
 
 /**
  * A C/C++ sizeof expression whose operand is an expression.
+ * ```
+ * if (sizeof(a) == sizeof(b)) { c = (b)a; }
+ * ```
  */
 class SizeofExprOperator extends SizeofOperator {
   SizeofExprOperator() { exists(Expr e | this.getChild(0) = e) }
@@ -611,6 +733,9 @@ class SizeofExprOperator extends SizeofOperator {
 
 /**
  * A C/C++ sizeof expression whose operand is a type name.
+ * ```
+ * int szlong = sizeof(int) == sizeof(long)? 4 : 8;
+ * ```
  */
 class SizeofTypeOperator extends SizeofOperator {
   SizeofTypeOperator() { sizeof_bind(underlyingElement(this), _) }
@@ -643,6 +768,9 @@ abstract class AlignofOperator extends Expr, @runtime_alignof {
 
 /**
  * A C++11 `alignof` expression whose operand is an expression.
+ * ```
+ * int addrMask = ~(alignof(expr) - 1);
+ * ```
  */
 class AlignofExprOperator extends AlignofOperator {
   AlignofExprOperator() { exists(Expr e | this.getChild(0) = e) }
@@ -662,6 +790,9 @@ class AlignofExprOperator extends AlignofOperator {
 
 /**
  * A C++11 `alignof` expression whose operand is a type name.
+ * ```
+ * bool proper_alignment = (alingof(T) == alignof(T[0[);
+ * ```
  */
 class AlignofTypeOperator extends AlignofOperator {
   AlignofTypeOperator() { sizeof_bind(underlyingElement(this), _) }
@@ -679,6 +810,10 @@ class AlignofTypeOperator extends AlignofOperator {
 
 /**
  * A C/C++ array to pointer conversion.
+ *
+ * The conversion is either implicit or underlies a particular cast.
+ * Please see **CStyleCast**, **StaticCast**,  **ConstCast**
+ * or **ReinterpretCast** for more information.
  */
 class ArrayToPointerConversion extends Conversion, @array_to_pointer {
   /** Gets a textual representation of this conversion. */