Regex lexer node

A lexer node using regular expressions for tokenization. More...

Functions
struct ec_node *	ec_node_re_lex (const char *id, struct ec_node *child)
int	ec_node_re_lex_add (struct ec_node *gen_node, const char *pattern, int keep, const char *attr_name)

Detailed Description

A lexer node using regular expressions for tokenization.

Configuration Schema

schema re_lex {
    list patterns  {
        description "The list of patterns elements.";
 
        dict  {
            description "A pattern element.";
 
            string pattern  {
                description "The pattern to match.";
            }
            bool keep  {
                description "Whether to keep or drop the string matching the regular expression.";
            }
            string attr  {
                description "The optional attribute name to attach.";
            }
        }
    }
    node child  {
        description "The child node.";
    }
}

Function Documentation

ec_node_re_lex()

struct ec_node * ec_node_re_lex	(	const char *	id,
		struct ec_node *	child )

Create a regex-based lexer node.

This node tokenizes the input using regular expressions added with ec_node_re_lex_add() and passes the resulting tokens to the child node.

Parameters

id	The node identifier.
child	The child node. It is consumed and will be freed when the parent is freed, or immediately on error.

Returns

The node, or NULL on error (errno is set).

ec_node_re_lex_add()

int ec_node_re_lex_add	(	struct ec_node *	gen_node,
		const char *	pattern,
		int	keep,
		const char *	attr_name )

Add a token pattern to a regex lexer node.

Parameters

gen_node	The regex lexer node.
pattern	The regular expression pattern for matching tokens.
keep	If non-zero, include matched tokens in the output; if zero, discard them.
attr_name	Optional attribute name to attach to matched tokens, or NULL.

Returns

0 on success, -1 on error (errno is set).