Abstract Syntax Tree

Kork parses the code into the following AST https://github.com/langchain-ai/kork/blob/main/kork/ast.py.

Below we’ll show a few of the utilities to parse and print the ast.

Parse

from kork.parser import parse

parse("x")

Program(stmts=(Variable(name='x'),))

parse("x = 1")

Program(stmts=(Assign(name='x', value=Literal(value=1)),))

parse(
    """
extern fn foo() -> Any # Comment

x = 1; // Comment
y = x * x + foo()
"""
)

Program(stmts=(ExternFunctionDef(name='foo', params=ParamList(params=[]), return_type='Any', implementation=None, doc_string=''), Assign(name='x', value=Literal(value=1)), Assign(name='y', value=Binary(left=Binary(left=Variable(name='x'), operator='*', right=Variable(name='x')), operator='+', right=FunctionCall(name='foo', args=[])))))

AstPrinter

The AST printer can be used to translate AST syntax into a string representation of the program.

This functionality is used to generate the prompt for the LLM as we’ll see later in the docs.

from kork import AstPrinter

program = parse(
    """
    extern fn foo() -> Any # Comment
x=1; // Comment
y=x*x + foo()
"""
)

program.stmts[0].params

ParamList(params=[])

print(AstPrinter().visit(program))

extern fn foo() -> Any
x = 1
y = x * x + foo()

Nodes

The nodes in the ast are in the ast module.

from kork.ast import FunctionCall, FunctionDef

?FunctionCall

Init signature: FunctionCall(name: 'str', args: 'Sequence[Expr]') -> None
Docstring:      Represent a function call.
File:           ~/src/kork/kork/ast.py
Type:           ABCMeta
Subclasses:     

?FunctionDef

Init signature:
FunctionDef(
    name: 'str',
    params: 'ParamList',
    body: 'Sequence[Union[Stmt, Expr]]',
    return_type: 'str',
) -> None
Docstring:      Represent a function definition with an implementation.
File:           ~/src/kork/kork/ast.py
Type:           ABCMeta
Subclasses: