std.ast Package

Function Description

The ast package contains the syntax parser of Cangjie source code and Cangjie syntax tree nodes, and provides syntactic parsing functions. It can parse lexical units (Tokens) of Cangjie source code to node objects of the abstract syntax tree.

The Cangjie ast package provides functions related to Macro With Context used to obtain the context information during macro expansion. In the nested macro scenario, an inner macro can call the library function assertParentContext(String) to ensure that the inner macro call is nested in a specific outer macro call. If the call of this function by the inner macro is not nested within the given outer macro call, the function throws an error. In addition, the insideParentContext(String) function is also used to check whether an inner macro call is nested in a specific outer macro call and return a Boolean value. Functions related to Macro With Context can only be directly called as functions, do not support variable assignment, and cannot be used as actual parameters or return values.

The functions related to Macro With Context are as follows:

API List

Function

Name	Description
assertParentContext(String)	Checks whether the current macro call is within a specific macro call. If the check result does not meet the expectation, the compiler displays an error message.
cangjieLex(String)	Converts a string to a value of the `Tokens` type.
cangjieLex(String, Bool)	Converts a string to a value of the `Tokens` type.
compareTokens(Tokens, Tokens)	Checks whether two `Tokens` are the same.
diagReport(DiagReportLevel, Tokens, String, String)	Specifies an error reporting API used to output error messages during macro expansion in the compilation process. `WARNING` and `ERROR` messages are supported.
getChildMessages(String)	Obtains information sent by a specific inner macro.
getTokenKind(UInt16)	Converts a sequence number of the lexical unit type to `TokenKind`.
insideParentContext(String)	Checks whether the current macro call is within a specific macro call and returns a Boolean value.
parseDecl(Tokens, String)	Parses a group of lexical units to obtain a node of the `Decl` type.
parseDeclFragment(Tokens, Int64)	Parses a group of lexical units to obtain a node of the `Decl` type and an index for continuing node parsing.
parseExpr(Tokens)	Parses a group of lexical units to obtain a node of the `Expr` type.
parseExprFragment(Tokens, Int64)	Parses a group of lexical units to obtain a node of the `Expr` type and an index for continuing node parsing.
parseProgram(Tokens)	Parses the source code of a single Cangjie file to obtain a node of the `Program` type.
setItem(String, Bool)	Sends information of the `Bool` type from an inner macro to an outer macro.
setItem(String, Int64)	Sends information of the `Int64` type from an inner macro to an outer macro.
setItem(String, String)	Sends information of the `String` type from an inner macro to an outer macro.

Interface

Name	Description
ToBytes	Provides the serialization function of the corresponding type.
ToTokens	Converts an instance type to the `Tokens` type. To support the quote interpolation operation, this interface must be implemented.

Class

Name	Description
Annotation	Specifies a built-in annotation node of the compiler.
Argument	Specifies an argument node in function call.
ArrayLiteral	Specifies an `Array` literal node.
AsExpr	Specifies a type check expression.
AssignExpr	Specifies an assignment expression node.
BinaryExpr	Specifies a binary operation expression node.
Block	Specifies a block node.
Body	Specifies a structure of the Class, Struct, or Interface type with an extension containing `{}` and a group of declaration nodes enclosed therein.
CallExpr	Specifies a function call node.
ClassDecl	Specifies a class definition node.
ConstPattern	Specifies a constant pattern node.
Constructor	Specifies a `Constructor` node of the `enum` type.
Decl	Specifies the parent class of all declaration nodes, which is inherited from the `Node` and provides the common API for all declaration nodes.
DoWhileExpr	Specifies a `do-while` expression.
EnumDecl	Specifies an `Enum` definition node.
EnumPattern	Specifies an enum pattern node.
ExceptTypePattern	Specifies a node used in exception pattern.
Expr	Specifies the parent class of all expression nodes, which is inherited from the `Node`.
ExtendDecl	Specifies an extension definition node.
ForInExpr	Specifies a `for-in` expression.
FuncDecl	Specifies a function definition node.
FuncParam	Specifies a function parameter node, including unnamed parameters and named parameters.
FuncType	Specifies a function type node.
GenericConstraint	Specifies a generic constraint node.
GenericParam	Specifies a type formal parameter node.
IfExpr	Specifies a condition expression.
ImportContent	Specifies an import item in the package import node.
ImportList	Specifies a package import node.
IncOrDecExpr	Specifies an expression that contains an auto-increment operator (`++`) or auto-decrement operator (`--`).
InterfaceDecl	Specifies an API definition node.
IsExpr	Specifies a type check expression.
JumpExpr	Specifies `break` and `continue` in the loop body of a loop expression.
LambdaExpr	Specifies a `Lambda` expression, which is an anonymous function.
LetPatternExpr	Specifies a deconstruction match node declared by `let`.
LitConstExpr	Specifies a constant expression node.
MacroDecl	Specifies a macro definition node.
MacroExpandDecl	Specifies a macro call node.
MacroExpandExpr	Specifies a macro call node.
MacroExpandParam	Specifies a macro call node.
MacroMessage	Records information sent by an inner macro.
MainDecl	Specifies a `main` function definition node.
MatchCase	Specifies a `case` node in a `match` expression.
MatchExpr	Specifies that a pattern matching expression implements pattern matching.
MemberAccess	Specifies a member access expression.
Modifier	Specifies that a definition has certain features. It is usually placed at the beginning of a definition.
Node	Specifies the parent class of all Cangjie syntax tree nodes.
OptionalExpr	Specifies an expression node with a question mark (?).
PackageHeader	Specifies a package declaration node.
ParenExpr	Specifies a parenthesis expression node, which is an expression enclosed in parentheses.
ParenType	Specifies a parenthesis type node.
Pattern	Specifies the parent class of all pattern matching nodes, which is inherited from the `Node`.
PrefixType	Specifies a prefix type node with a question mark (?).
PrimaryCtorDecl	Specifies a primary constructor node.
PrimitiveType	Specifies a primitive type node.
PrimitiveTypeExpr	Specifies a primitive type expression node.
Program	Specifies a Cangjie source code file node.
PropDecl	Specifies a property definition node.
QualifiedType	Specifies a user-defined member type.
QuoteExpr	Specifies a `quote` expression node.
QuoteToken	Specifies any valid `token` in a `quote`expression node.
RangeExpr	Specifies an expression that contains range operators.
RefExpr	Specifies an expression node related to a node of a user-defined type.
RefType	Specifies a user-defined type node.
ReturnExpr	Specifies a `return` expression node.
SpawnExpr	Specifies a `Spawn` expression.
StructDecl	Specifies a `Struct` node.
SubscriptExpr	Specifies an index access expression.
SynchronizedExpr	Specifies a `synchronized` expression.
ThisType	Specifies a `This` type node.
ThrowExpr	Specifies a `throw` expression node.
Tokens	Specifies a type for encapsulating `Token` sequences.
TokensIterator	Implements the iterator function of `Tokens`.
TrailingClosureExpr	Specifies a trailing `Lambda` node.
TryExpr	Specifies a `try` expression node.
TupleLiteral	Specifies a tuple literal node.
TuplePattern	Specifies a Tuple pattern node.
TupleType	Specifies a tuple type node.
TypeAliasDecl	Specifies a type alias node.
TypeConvExpr	Specifies a type conversion expression.
TypeNode	Specifies the parent class of all type nodes, which is inherited from `Node`.
TypePattern	Specifies a type pattern node.
UnaryExpr	Specifies a unary operation expression node.
VArrayExpr	Specifies a `VArray` instance node.
VArrayType	Specifies a `VArray` type node.
VarDecl	Specifies a variable definition node.
VarOrEnumPattern	Specifies a node when the pattern identifier is an `Enum` constructor.
VarPattern	Specifies a binding pattern node.
Visitor	Specifies an abstract class that defines default `visit` functions for accessing different types of AST nodes.
WhileExpr	Specifies a `while` expression.
WildcardExpr	Specifies a wildcard expression node.
WildcardPattern	Specifies a wildcard pattern node.

Enumeration

Name	Description
DiagReportLevel	Specifies information levels supported by an error reporting API. `ERROR` and `WARNING` are supported.
ImportKind	Specifies the type of an import statement, including single import, alias import, full import, and multi-import.
TokenKind	Specifies all lexical structures in Cangjie compilation, including symbols, keywords, identifiers, and line breaks.

Struct

Name	Description
Position	Specifies the data structure of location information, including the file ID, row number, and column number.
Token	Specifies the lexical unit type.

Exception Class

Name	Description
ASTException	Specifies an exception class for the ast library, which is used when an exception occurs during ast library invocation.
MacroContextException	Specifies a context macro exception class for the ast library, which is used when an exception occurs in context macro-related APIs.
ParseASTException	Specifies a parsing exception class for the ast library, which is used when an exception occurs during node parsing.