classLr0Builder

packages/sql-parser/src/Automaton/Lr0Builder.php:19

final class Lr0Builder

Restricted visibility: declared "@visibility root". Code outside that scope must not name this declaration.

Builds the LR(0) automaton of a grammar from kernel items alone.

A state is identified by its kernel. Its closure is never materialised: the transitions out of it are computed from the kernel items and the precomputed closure index, which keeps grammars with thousands of rules tractable.

Methods§

public function build(Grammar $grammar): Lr0Automaton

source §

Builds the automaton.

Parameters

$grammar Grammar Grammar to build for

Returns

Lr0Automaton The states in the order they were discovered, the start state first

Test cases 5

Called from 1

method-call SqlParser\Automaton\ParseTableBuilder::build() packages/sql-parser/src/Automaton/ParseTableBuilder.php:45

Calls 9

new ClosureIndex line 30
function-call intdiv line 40
method-call ClosureIndex::startsWith() line 50
method-call ClosureIndex::emptyRules() line 55
function-call array_keys line 61
function-call sort line 62
function-call implode line 63
function-call count line 65
new Lr0Automaton line 76

Test cases 7§

Test cases that cover or call this symbol, from the coverage report and from the analyzed test sources.

Dedicated tests 2

Other tests reaching this symbol 5

LookaheadSetsTest::testOfFollowsTheTextbookGrammar calls
LookaheadSetsTest::testOfReadsThroughNullableNonterminals calls
LookaheadSetsTest::testReads calls
ParseTableBuilderTest calls
LrParserTest calls

Relations§

Instantiated in 1

new SqlParser\Automaton\ParseTableBuilder::__construct() packages/sql-parser/src/Automaton/ParseTableBuilder.php:32

Method calls 1

method-call SqlParser\Automaton\ParseTableBuilder::build() packages/sql-parser/src/Automaton/ParseTableBuilder.php:45

Type declarations 1

type SqlParser\Automaton\ParseTableBuilder packages/sql-parser/src/Automaton/ParseTableBuilder.php:32