AST Support code shared by TreeParser and Parser.
We use delegation to share code (and have only one
bit of code to maintain) rather than subclassing
or superclassing (forces AST support code to be
loaded even when you don't want to do AST stuff).
Typically, setASTNodeType is used to specify the
homogeneous type of node to create, but you can override
create to make heterogeneous nodes etc...
addASTChild
public void addASTChild(ASTPair currentAST,
AST child)
Add a child to the current AST
create
public AST create()
Create a new empty AST node; if the user did not specify
an AST node type, then create a default one: CommonAST.
create
protected AST create(Class c)
- 2.7.2
create
public AST create(String className)
- 2.7.2
create
public AST create(Token tok,
String className)
ANTLR generates reference to this when you reference a token
that has a specified heterogeneous AST node type. This is
also a special case node creation routine for backward
compatibility. Before, ANTLR generated "new T(tokenObject)"
and so I must call the appropriate constructor not T().
- 2.7.2
create
public AST create(AST tr)
Create a new empty AST node; if the user did not specify
an AST node type, then create a default one: CommonAST.
create
public AST create(int type)
create
public AST create(int type,
String txt)
create
public AST create(int type,
String txt,
String className)
Create an AST node with the token type and text passed in, but
with a specific Java object type. Typically called when you
say @[PLUS,"+",PLUSNode] in an antlr action.
- 2.7.2
createUsingCtor
protected AST createUsingCtor(Token token,
String className)
- 2.7.2
dup
public AST dup(AST t)
Copy a single node with same Java AST objec type.
Ignore the tokenType->Class mapping since you know
the type of the node, t.getClass(), and doing a dup.
clone() is not used because we want all AST creation
to go thru the factory so creation can be
tracked. Returns null if t is null.
dupList
public AST dupList(AST t)
Duplicate tree including siblings of root.
dupTree
public AST dupTree(AST t)
Duplicate a tree, assuming this is a root node of a tree--
duplicate that node and what's below; ignore siblings of root node.
error
public void error(String e)
To change where error messages go, can subclass/override this method
and then setASTFactory in Parser and TreeParser. This method removes
a prior dependency on class antlr.Tool.
getASTNodeType
public Class getASTNodeType(int tokenType)
For a given token type, what is the AST node object type to create
for it?
- 2.7.2
getTokenTypeToASTClassMap
public Hashtable getTokenTypeToASTClassMap()
make
public AST make(AST nodes)
Make a tree from a list of nodes. The first element in the
array is the root. If the root is null, then the tree is
a simple list not a tree. Handles null children nodes correctly.
For example, build(a, b, null, c) yields tree (a b c). build(null,a,b)
yields tree (nil a b).
make
public AST make(ASTArray nodes)
Make a tree from a list of nodes, where the nodes are contained
in an ASTArray object
makeASTRoot
public void makeASTRoot(ASTPair currentAST,
AST root)
Make an AST the root of current AST
setASTNodeClass
public void setASTNodeClass(Class c)
setASTNodeClass
public void setASTNodeClass(String t)
setASTNodeType
public void setASTNodeType(String t)
since 2.7.1
Specify the type of node to create during tree building.
setTokenTypeASTNodeType
public void setTokenTypeASTNodeType(int tokenType,
String className)
throws IllegalArgumentException
Specify an "override" for the Java AST object created for a
specific token. It is provided as a convenience so
you can specify node types dynamically. ANTLR sets
the token type mapping automatically from the tokens{...}
section, but you can change that mapping with this method.
ANTLR does it's best to statically determine the node
type for generating parsers, but it cannot deal with
dynamic values like #[LT(1)]. In this case, it relies
on the mapping. Beware differences in the tokens{...}
section and what you set via this method. Make sure
they are the same.
Set className to null to remove the mapping.
- 2.7.2
setTokenTypeToASTClassMap
public void setTokenTypeToASTClassMap(Hashtable tokenTypeToClassMap)