2 C Syntax

This library provides data types representing C abstract syntax, a C parser, and macros for constructing C abstract syntax with a convenient parenthesized syntax. It can be required via:

(require (planet dherman/c:1:0/syntax))

2.1 Expressions

(struct expr:lit (type value))

type : symbol?

value : any

(struct expr:binop (op left right))

op : symbol?

left : expr?

right : expr?

2.2 Declarations

(struct decl:type:def (root defs))

root : type?

defs : (listof (cons symbol? #f))

(struct decl:type:tagged (type))

type : (or/c type:struct? type:union? type:enum?)

2.3 Types

(struct type:ref (name))

name : symbol?

(struct type:struct (tag fields))

tag : (optional symbol?)

fields : (listof (cons symbol? type?))

(struct type:union (tag variants))

tag : (optional symbol?)

variants : (listof (cons symbol? type?))

(struct type:enum (tag variants))

tag : (optional symbol?)

variants : list?

(struct type:array (type size))

type : type?

size : expr?

(struct type:pointer (type))

type : type?

(struct type:function (return args))

return : type?

args : (listof type?)

2.4 Utility Functions

(type? x) → boolean?

x : any

Determines whether x is a type.

(expr? x) → boolean?

x : any

Determines whether x is an expression.

(decl? x) → boolean?

x : any

Determines whether x is a declaration.

2.5 S-Expression Syntax

(typedef type alias-id)   type   =   struct     |   type-id

(struct tag-id) (struct tag-id (struct-field ...)) (struct (struct-field ...))   struct-field   =   [type field-id]     |   field-id

(union tag-id) (union tag-id (union-variant ...)) (union (union-variant ...))   union-variant   =   [type variant-id]     |   variant-id

(enum tag-id) (enum tag-id (enum-variant ...)) (enum (enum-variant ...))   enum-variant   =   [variant-id expr]     |   variant-id

(array type size) → type:array?

type : type?

size : expr?

(pointer type) → type:pointer?

type : type?

2.6 Parsing

(parse-decl in) → decl?

in : (or/c input-port? string? path?)

Parses a C declaration.

(parse-decls in) → (listof decl?)

in : (or/c input-port? string? path?)

Parses a sequence of C declarations.

2.7 C Reader

The module

(require (planet dherman/c:1:0/reader))

provides a reader for C syntax. Using this reader, it is possible to embed C syntax directly into Scheme programs. For example:

(define decls

#reader (planet dherman/c/reader) {

typedef int INT;

struct tm {

INT tm_sec;

INT tm_min;

INT tm_hour;

INT tm_mday;

INT tm_mon;

INT tm_year;

INT tm_wday;

INT tm_yday;

INT tm_isdst;

};

})

The C reader produces a quoted literal list of declarations.