libflint/docs/string.md

string

C string helpers

Functions

find_substrings

Finds the indexes of all locations of the given needle in the haystack. The returned array of size_t is allocated by this function and memory cleanup is managed by the user. num_substrings is a pointer to a pre-allocated size_t that will be modified to contain the number of found substrings and subsequently the size of the returned array of size_t. Returns NULL and prints to stderr if there is an error.

size_t *find_substrings(const char* haystack, const char* needle, size_t *num_substrings);

/* Usage */
const char* haystack = "One two three two";
const char* needle = "two";
size_t subs_sz = 0;

size_t *subs = find_substrings(haystack, needle, &subs_sz);
// subs: [ 4, 14 ]
// subs_sz: 2

free(subs);

substr

Extracts a substring at a specific index and length. This function returns a copy of the substring in a heap allocated buffer that the user is responsible for freeing. Returns NULL and prints to stderr if there is an error.

const char* substr(const char* str, size_t idx, size_t len);

/* Usage */
const char *s = substr("One two three", 4, 3);
assert(strcmp(s, "two") == 0);
free(s);