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replace_eval


Description:

public string replace_eval (string str, ssize_t string_len, int start_position, RegexMatchFlags match_options = 0, RegexEvalCallback eval) throws RegexError

Replaces occurrences of the pattern in regex with the output of eval for that occurrence.

Setting start_position differs from just passing over a shortened string and setting G_REGEX_MATCH_NOTBOL in the case of a pattern that begins with any kind of lookbehind assertion, such as "\b".

The following example uses g_regex_replace_eval() to replace multiple strings at once:


static gboolean
eval_cb (const GMatchInfo *info,
GString *res,
gpointer data)
{
gchar *match;
gchar *r;

match = g_match_info_fetch (info, 0);
r = g_hash_table_lookup ((GHashTable *)data, match);
g_string_append (res, r);
g_free (match);

return FALSE;
}

// ...

GRegex *reg;
GHashTable *h;
gchar *res;

h = g_hash_table_new (g_str_hash, g_str_equal);

g_hash_table_insert (h, "1", "ONE");
g_hash_table_insert (h, "2", "TWO");
g_hash_table_insert (h, "3", "THREE");
g_hash_table_insert (h, "4", "FOUR");

reg = g_regex_new ("1|2|3|4", 0, 0, NULL);
res = g_regex_replace_eval (reg, text, -1, 0, 0, eval_cb, h, NULL);
g_hash_table_destroy (h);

// ...

Parameters:

regex a GRegex structure from g_regex_new()
string string to perform matches against. [array length=string_len]
string_len the length of string, or -1 if string is nul-terminated
start_position starting index of the string to match
match_options options for the match
eval a function to call for each match
user_data user data to pass to the function
error location to store the error occuring, or NULL to ignore errors

Returns:

a newly allocated string containing the replacements