Function replace_regex_scan_cb

src/arithmetic/string_funcs/string_funcs.c:378–400

} replace_regex_scan_cb_args;

static int replace_regex_scan_cb(int n, int pos, OnigRegion *region, void *arg) {
	replace_regex_scan_cb_args *args = (replace_regex_scan_cb_args *)arg;
	const char *str = args->str;
	assert(region->num_regs > 0);

	// reallocate new str size
	int str_copy_len = region->beg[0] - args->str_ind;
	int str_size = args->res_len + str_copy_len + args->replacement_len + 1;
	args->res = rm_realloc(args->res, str_size);

	// copy the string between the last match and the current match
	memcpy(args->res + args->res_len, str + args->str_ind, str_copy_len);
	args->str_ind = region->end[0];
	args->res_len += str_copy_len;

	// copy the replacement string
	memcpy(args->res + args->res_len, args->replacement, args->replacement_len);
	args->res_len += args->replacement_len;

	args->res[args->res_len] = '\0';

	return 0;
}

// given a string and a regular expression,
// return a string after replacing each regex match with a given replacement.