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Updated some wording in the documentation

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Sam Harwell 2014-01-23 06:47:26 -06:00
parent 58cc8f28d7
commit 0949ff8249
1 changed files with 14 additions and 19 deletions
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33
runtime/Java/src/org/antlr/v4/runtime/atn/ParserATNSimulator.java
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@ -233,22 +233,17 @@ import java.util.Set;
* way it will work because it's not doing a test and set operation.</p>
*
* <p>
* <strong>Starting with SLL then failing to combined SLL/LL</strong></p>
* <strong>Starting with SLL then failing to combined SLL/LL (Two-Stage
* Parsing)</strong></p>
*
* <p>
* Sam pointed out that if SLL does not give a syntax error, then there is no
* point in doing full LL, which is slower. We only have to try LL if we get a
* syntax error. For maximum speed, Sam starts the parser with pure SLL
* mode:</p>
* syntax error. For maximum speed, Sam starts the parser set to pure SLL
* mode with the {@link BailErrorStrategy}:</p>
*
* <pre>
* parser.{@link Parser#getInterpreter() getInterpreter()}.{@link #setSLL setSLL(true)};
* </pre>
*
* <p>
* and with the bail error strategy:</p>
*
* <pre>
* parser.{@link Parser#setErrorHandler setErrorHandler}(new {@link BailErrorStrategy}());
* </pre>
*
@ -257,16 +252,16 @@ import java.util.Set;
* error, we need to retry with the combined SLL/LL strategy.</p>
*
* <p>
* The reason this works is as follows. If there are no SLL conflicts then the
* grammar is SLL for sure, at least for that input set. If there is an SLL
* conflict, the full LL analysis must yield a set of ambiguous alternatives
* that is no larger than the SLL set. If the LL set is a singleton, then the
* grammar is LL but not SLL. If the LL set is the same size as the SLL set, the
* decision is SLL. If the LL set has size &gt; 1, then that decision is truly
* ambiguous on the current input. If the LL set is smaller, then the SLL
* conflict resolution might choose an alternative that the full LL would rule
* out as a possibility based upon better context information. If that's the
* case, then the SLL parse will definitely get an error because the full LL
* The reason this works is as follows. If there are no SLL conflicts, then the
* grammar is SLL (at least for that input set). If there is an SLL conflict,
* the full LL analysis must yield a set of viable alternatives which is a
* subset of the alternatives reported by SLL. If the LL set is a singleton,
* then the grammar is LL but not SLL. If the LL set is the same size as the SLL
* set, the decision is SLL. If the LL set has size &gt; 1, then that decision
* is truly ambiguous on the current input. If the LL set is smaller, then the
* SLL conflict resolution might choose an alternative that the full LL would
* rule out as a possibility based upon better context information. If that's
* the case, then the SLL parse will definitely get an error because the full LL
* analysis says it's not viable. If SLL conflict resolution chooses an
* alternative within the LL set, them both SLL and LL would choose the same
* alternative because they both choose the minimum of multiple conflicting