AST library

The (scheme cyclone ast) library defines abstract syntax tree types used during compilation.

This library is used internally by the compiler and its API may change at any time.

• ast:make-lambda
• ast:lambda?
• ast:lambda-id
• ast:lambda-args
• ast:set-lambda-args!
• ast:lambda-body
• ast:set-lambda-body!
• ast:ast->sexp
• ast:sexp->ast
• ast:ast->pp-sexp

ast:make-lambda

(ast:make-lambda args body)
(ast:make-lambda args body cont)

Create an instance of the ast-lambda record type.

This data type is at the center of this module and consists of the following data:

• id - Unique numeric ID assigned to each lambda
• args - Arguments to the lambda. This may be one of:
  • symbol indicating a function takes any number of arguments
  • list of symbols corresponding to each of a fixed number of arguments to the function
  • improper list indicating a function taking a fixed number of required arguments as well as an arbitrary number of optional arguments
• body - Expression in the function body of the lambda
• cont - Boolean indicating whether the lambda has a continuation

ast:make-lambda automatically assigns the id field to a unique value.

ast:lambda?

(ast:lambda? obj)

Predicate indicating whether obj is an ast-lambda object.

ast:lambda-id

(ast:lambda-id lambda-obj)

Return the id field of the given ast-lambda object.

ast:lambda-args

(ast:lambda-args lambda-obj)

Return the args field of the given ast-lambda object.

ast:set-lambda-args!

(ast:set-lambda-args! lambda-obj args)

Change the args field of the given ast-lambda object.

ast:lambda-body

(ast:lambda-body lambda-obj)

Return the body field of the given ast-lambda object.

ast:set-lambda-body!

(ast:set-lambda-body! lambda-obj body)

Change the body field of the given ast-lambda object.

ast:ast->sexp

(ast:ast->sexp exp)

Convert an abstract syntax tree exp back into an equivalent expression consisting of standard Scheme S-expressions. IE: lambda forms instead of ast-lambda objects.

ast:sexp->ast

(ast:sexp->ast exp)

Convert a standard Scheme S-expression tree containing lambda forms into an equivalent abstract syntax tree consisting of equivalent ast-lambda objects.

ast:ast->pp-sexp

(ast:ast->pp-sexp exp)

Transform an abstract syntax tree into one that prints more cleanly.