meta_language/grammar/
concepts.rs

1//! Concept-ontology alignment for grammar algebra nodes.
2
3use super::{Grammar, GrammarExpr, GrammarRule};
4use crate::link_network::LinkNetwork;
5
6/// A grammar-algebra concept with a stable id and per-format surface forms.
7#[derive(Clone, Copy, Debug, PartialEq, Eq)]
8pub struct GrammarConcept {
9    /// Stable language-free concept identifier.
10    pub id: &'static str,
11    /// Human-readable definition of the grammar construct.
12    pub definition: &'static str,
13    /// Concrete syntax examples keyed by grammar format.
14    pub syntax: &'static [(&'static str, &'static str)],
15}
16
17/// Grammar construct concepts aligned with [`GrammarExpr`] variants and rules.
18pub const GRAMMAR_CONCEPTS: &[GrammarConcept] = &[
19    GrammarConcept {
20        id: "grammar.rule",
21        definition: "A named grammar production that binds a non-terminal to an expression.",
22        syntax: &[
23            ("bnf", "::="),
24            ("ebnf", "="),
25            ("abnf", "="),
26            ("peg", "="),
27            ("meta-language", "rule"),
28        ],
29    },
30    GrammarConcept {
31        id: "grammar.sequence",
32        definition: "An ordered concatenation of grammar expressions.",
33        syntax: &[
34            ("bnf", "a b"),
35            ("ebnf", "a , b"),
36            ("peg", "a b"),
37            ("gbnf", "a b"),
38            ("meta-language", "sequence"),
39        ],
40    },
41    GrammarConcept {
42        id: "grammar.ordered-choice",
43        definition: "A prioritized grammar alternative where earlier matches win.",
44        syntax: &[("peg", "/"), ("meta-language", "ordered choice")],
45    },
46    GrammarConcept {
47        id: "grammar.unordered-choice",
48        definition: "A grammar alternative whose branches are not semantically prioritized.",
49        syntax: &[
50            ("bnf", "|"),
51            ("ebnf", "|"),
52            ("abnf", "/"),
53            ("antlr", "|"),
54            ("lark", "|"),
55            ("meta-language", "choice"),
56        ],
57    },
58    GrammarConcept {
59        id: "grammar.repetition",
60        definition: "A counted repetition with explicit minimum and optional maximum bounds.",
61        syntax: &[
62            ("ebnf", "{ }"),
63            ("abnf", "m*n"),
64            ("gbnf", "{m,n}"),
65            ("meta-language", "repeat"),
66        ],
67    },
68    GrammarConcept {
69        id: "grammar.zero-or-more",
70        definition: "A repetition that accepts zero or more occurrences.",
71        syntax: &[
72            ("peg", "*"),
73            ("ebnf", "{ }"),
74            ("antlr", "*"),
75            ("lark", "*"),
76            ("gbnf", "*"),
77        ],
78    },
79    GrammarConcept {
80        id: "grammar.one-or-more",
81        definition: "A repetition that accepts one or more occurrences.",
82        syntax: &[
83            ("peg", "+"),
84            ("antlr", "+"),
85            ("lark", "+"),
86            ("gbnf", "+"),
87            ("meta-language", "one or more"),
88        ],
89    },
90    GrammarConcept {
91        id: "grammar.optional",
92        definition: "An expression that may be present or absent.",
93        syntax: &[
94            ("ebnf", "[ ]"),
95            ("abnf", "[ ]"),
96            ("peg", "?"),
97            ("antlr", "?"),
98            ("lark", "?"),
99        ],
100    },
101    GrammarConcept {
102        id: "grammar.terminal",
103        definition: "A literal terminal token matched directly in the input.",
104        syntax: &[
105            ("bnf", "\"lit\""),
106            ("ebnf", "\"lit\""),
107            ("abnf", "%i\"lit\""),
108            ("peg", "\"lit\""),
109            ("lark", "\"lit\""),
110            ("tree-sitter", "token"),
111        ],
112    },
113    GrammarConcept {
114        id: "grammar.non-terminal",
115        definition: "A reference to another named grammar rule.",
116        syntax: &[
117            ("bnf", "<name>"),
118            ("ebnf", "name"),
119            ("peg", "name"),
120            ("antlr", "name"),
121            ("lark", "name"),
122            ("meta-language", "non-terminal"),
123        ],
124    },
125    GrammarConcept {
126        id: "grammar.char-class",
127        definition: "A set of characters accepted at one input position.",
128        syntax: &[
129            ("peg", "[a-z]"),
130            ("antlr", "[a-z]"),
131            ("lark", "/[a-z]/"),
132            ("gbnf", "[^...]"),
133            ("meta-language", "character class"),
134        ],
135    },
136    GrammarConcept {
137        id: "grammar.char-range",
138        definition: "An inclusive range between two character endpoints.",
139        syntax: &[
140            ("abnf", "%x30-39"),
141            ("lark", "\"a\"..\"z\""),
142            ("meta-language", "'a'..='z'"),
143        ],
144    },
145    GrammarConcept {
146        id: "grammar.any-char",
147        definition: "A wildcard grammar expression that accepts any single character.",
148        syntax: &[
149            ("peg", "."),
150            ("lark", "."),
151            ("gbnf", "."),
152            ("meta-language", "any"),
153        ],
154    },
155    GrammarConcept {
156        id: "grammar.positive-predicate",
157        definition:
158            "A positive lookahead predicate that tests an expression without consuming input.",
159        syntax: &[("peg", "&e"), ("meta-language", "and predicate")],
160    },
161    GrammarConcept {
162        id: "grammar.negative-predicate",
163        definition: "A negative lookahead predicate that rejects when an expression would match.",
164        syntax: &[("peg", "!e"), ("meta-language", "not predicate")],
165    },
166    GrammarConcept {
167        id: "grammar.capture",
168        definition: "A labelled or anonymous capture of a grammar subexpression.",
169        syntax: &[
170            ("meta-language", "name:e"),
171            ("antlr", "label=e"),
172            ("lark", "name:e"),
173        ],
174    },
175    GrammarConcept {
176        id: "grammar.empty",
177        definition: "A grammar expression that accepts the empty string.",
178        syntax: &[
179            ("bnf", "empty alternative"),
180            ("ebnf", "empty alternative"),
181            ("meta-language", "empty"),
182        ],
183    },
184];
185
186/// Concept id for a [`GrammarExpr`] variant.
187#[must_use]
188pub const fn grammar_expr_concept_id(expr: &GrammarExpr) -> &'static str {
189    match expr {
190        GrammarExpr::Empty => "grammar.empty",
191        GrammarExpr::Terminal(_) | GrammarExpr::TerminalInsensitive(_) => "grammar.terminal",
192        GrammarExpr::CharRange(_, _) => "grammar.char-range",
193        GrammarExpr::CharClass { .. } => "grammar.char-class",
194        GrammarExpr::AnyChar => "grammar.any-char",
195        GrammarExpr::NonTerminal(_) => "grammar.non-terminal",
196        GrammarExpr::Choice { ordered: true, .. } => "grammar.ordered-choice",
197        GrammarExpr::Choice { ordered: false, .. } => "grammar.unordered-choice",
198        GrammarExpr::Sequence(_) => "grammar.sequence",
199        GrammarExpr::Optional(_) => "grammar.optional",
200        GrammarExpr::ZeroOrMore(_) => "grammar.zero-or-more",
201        GrammarExpr::OneOrMore(_) => "grammar.one-or-more",
202        GrammarExpr::Repeat { .. } => "grammar.repetition",
203        GrammarExpr::And(_) => "grammar.positive-predicate",
204        GrammarExpr::Not(_) => "grammar.negative-predicate",
205        GrammarExpr::Capture { .. } => "grammar.capture",
206    }
207}
208
209/// Concept id for a rule: its explicit concept, or its top-level expression concept.
210#[must_use]
211pub fn rule_concept_id(rule: &GrammarRule) -> Option<&str> {
212    rule.concept()
213        .map_or_else(|| Some(grammar_expr_concept_id(rule.expr())), Some)
214}
215
216/// Fills missing rule-level concept alignments from each rule's top-level expression.
217pub fn annotate_grammar_concepts(grammar: &mut Grammar) {
218    for rule in &mut grammar.rules {
219        if rule.concept.is_none() {
220            rule.concept = Some(grammar_expr_concept_id(&rule.expr).to_owned());
221        }
222    }
223}
224
225impl LinkNetwork {
226    /// Seeds only the grammar-construct concept ontology layer.
227    #[must_use]
228    pub fn seed_grammar_concept_ontology(&mut self) -> usize {
229        for concept in GRAMMAR_CONCEPTS {
230            let concept_link = self.intern_concept(concept.id, Some(concept.definition));
231
232            for (language, syntax) in concept.syntax {
233                self.insert_concept_syntax_mapping(
234                    concept_link,
235                    concept.id,
236                    language,
237                    syntax,
238                    true,
239                );
240            }
241        }
242
243        GRAMMAR_CONCEPTS.len()
244    }
245}
meta_language/grammar/concepts.rs

meta_language/grammar/
concepts.rs
