pattern_class

The currset set of pattern classes you can use when matching a macro pattern with $pat:<class>:

base  (alias for Program)
expr  (alias for AssignmentExpression)
ident (alias for PrimaryExpression)
lit   (alias for PrimaryExpression)
Program 
LogicalANDExpression 
PrimaryExpression 
VariableDeclarationList 
StatementList 
SourceElements
FunctionExpression 
ExpressionStatement 
IfStatement 
BreakStatement 
ContinueStatement 
WithStatement 
SwitchStatement 
ReturnStatement 
ThrowStatement 
TryStatement 
WhileStatement 
ForStatement 
VariableDeclaration 
ArrayExpression 
ObjectExpression 
SequenceExpression 
AssignmentExpression 
ConditionalExpression 
NewExpression 
CallExpression 
Block