Supports (, [, {, and < as brace characters.

This utility is intended as a simple, lightweight config loader for development utilities, not a full-fledged user-facing parser with meaningful error messages. It was originally built to use with gode generators.

typedef struct sexp { char type; // 0 = list, 1 = literal char brace; // '(', '[', '{', or '<' char* str; // scalar value; NULL when VEC_len(args) > 0 VEC(struct sexp*) args; } sexp;

sexp* sexp_parse(char* source)

Parses the NULL-terminated source string. Syntax must be valid. The resulting tree does not depend on the memory inside source.

sexp* sexp_parse_file(char* path)

Parses the file at path. Syntax must be valid. The resulting tree does not depend on the memory inside source.

void sexp_free(sexp* x)

Frees the entire contents of x recursively.

void sexp_print(int fd, sexp* x)

Recursively prints the contents of x to the file descriptor fd.

sexp* sexp_arg(sexp* x, size_t argn)

O(1)

Returns the nth argment from the list inside x. Returns NULL if called on a scalar value or if x is NULL.

int64_t sexp_int(sexp* x, size_t argn)

O(1)

Returns the nth argment from the list inside x converted to a signed integer using strtol(y->str, NULL, 0). If called on a scalar value, the value is converted and argn is ignored. Returns 0 if x is NULL.

uint64_t sexp_uint(sexp* x, size_t argn)

O(1)

Returns the nth argment from the list inside x converted to an unsigned integer using strtoul(y->str, NULL, 0). If called on a scalar value, the value is converted and argn is ignored. Returns 0 if x is NULL.

float sexp_float(sexp* x, size_t argn)

O(1)

Returns the nth argment from the list inside x converted to a float using strtof(). If called on a scalar value, the value is converted and argn is ignored. Returns 0 if x is NULL.

double sexp_double(sexp* x, size_t argn)

O(1)

Returns the nth argment from the list inside x converted to a double using strtod(). If called on a scalar value, the value is converted and argn is ignored. Returns 0 if x is NULL.

char* sexp_str(sexp* x, size_t argn)

O(1)

Returns the internal string pointer for the nth argment from the list inside x. If called on a scalar value, the value's pointer is returned. Returns NULL if x is NULL.

char* sexp_str(sexp* x, size_t argn)

O(1)

Returns a newly-allocated copy of the string for the nth argment from the list inside x. If called on a scalar value, the a copy of the value's string is returned. Returns NULL if x is NULL.

Simple S-Expression Parser