2 tre-ast.h - Abstract syntax tree (AST) definitions
4 This software is released under a BSD-style license.
5 See the file LICENSE for details and copyright.
14 #include "tre-internal.h"
15 #include "tre-compile.h"
17 /* The different AST node types. */
25 /* Special subtypes of TRE_LITERAL. */
26 #define EMPTY -1 /* Empty leaf (denotes empty string). */
27 #define ASSERTION -2 /* Assertion leaf. */
28 #define TAG -3 /* Tag leaf. */
29 #define BACKREF -4 /* Back reference leaf. */
30 #define PARAMETER -5 /* Parameter. */
32 #define IS_SPECIAL(x) ((x)->code_min < 0)
33 #define IS_EMPTY(x) ((x)->code_min == EMPTY)
34 #define IS_ASSERTION(x) ((x)->code_min == ASSERTION)
35 #define IS_TAG(x) ((x)->code_min == TAG)
36 #define IS_BACKREF(x) ((x)->code_min == BACKREF)
37 #define IS_PARAMETER(x) ((x)->code_min == PARAMETER)
40 /* A generic AST node. All AST nodes consist of this node on the top
41 level with `obj' pointing to the actual content. */
43 tre_ast_type_t type; /* Type of the node. */
44 void *obj; /* Pointer to actual node. */
49 tre_pos_and_tags_t *firstpos;
50 tre_pos_and_tags_t *lastpos;
54 /* A "literal" node. These are created for assertions, back references,
55 tags, matching parameter settings, and all expressions that match one
65 tre_ctype_t *neg_classes;
68 /* A "catenation" node. These are created when two regexps are concatenated.
69 If there are more than one subexpressions in sequence, the `left' part
70 holds all but the last, and `right' part holds the last subexpression
71 (catenation is left associative). */
74 tre_ast_node_t *right;
77 /* An "iteration" node. These are created for the "*", "+", "?", and "{m,n}"
80 /* Subexpression to match. */
82 /* Minimum number of consecutive matches. */
84 /* Maximum number of consecutive matches. */
86 /* If 0, match as many characters as possible, if 1 match as few as
87 possible. Note that this does not always mean the same thing as
88 matching as many/few repetitions as possible. */
89 unsigned int minimal:1;
90 /* Approximate matching parameters (or NULL). */
94 /* An "union" node. These are created for the "|" operator. */
97 tre_ast_node_t *right;
101 tre_ast_new_node(tre_mem_t mem, tre_ast_type_t type, size_t size);
104 tre_ast_new_literal(tre_mem_t mem, int code_min, int code_max, int position);
107 tre_ast_new_iter(tre_mem_t mem, tre_ast_node_t *arg, int min, int max,
111 tre_ast_new_union(tre_mem_t mem, tre_ast_node_t *left, tre_ast_node_t *right);
114 tre_ast_new_catenation(tre_mem_t mem, tre_ast_node_t *left,
115 tre_ast_node_t *right);
119 tre_ast_print(tre_ast_node_t *tree);
121 /* XXX - rethink AST printing API */
123 tre_print_params(int *params);
124 #endif /* TRE_DEBUG */
126 #endif /* TRE_AST_H */