Bugzilla – Full Text Bug Listing
| Summary: | UI Parser Hangs up | ||
|---|---|---|---|
| Product: | [Modeling] TMF | Reporter: | Christian Dietrich <christian.dietrich.opensource> |
| Component: | Xtext | Assignee: | Project Inbox <tmf.xtext-inbox> |
| Status: | NEW --- | QA Contact: | |
| Severity: | normal | ||
| Priority: | P3 | CC: | benjamin.schwertfeger, sebastian.zarnekow, sven.efftinge |
| Version: | unspecified | Flags: | sebastian.zarnekow:
juno+
|
| Target Milestone: | --- | ||
| Hardware: | PC | ||
| OS: | Windows XP | ||
| Whiteboard: | |||
The handling of syntactic predicates leads to duplicate parsing. In the generated Parser is a method like this:
rule__NavStatement__Group_1__5__Impl()
...
if ( (LA5_0==19) ) {
if ( (synpred6_InternalMyDsl()) ) {
alt5=1;
}
}
switch (alt5) {
case 1 : ...
rule__NavStatement__Group_1_5__0();
Where synpred6_InternalMyDsl also calls the rule rule__NavStatement__Group_1_5__0. Because the result is not cached you get a O^2 runtime for each recursive/hierarchical usage of syntactic predicates.
Workaround:
If possible remove the syntactic predicate and ignore the warning while generating.
Please try to enable memoization for the ui parser. (In reply to comment #2) > Please try to enable memoization for the ui parser. For the given example it works like a charm. Thanks for the hint. |
Build Identifier: 2.0.0 2.1.0 Having following (largely simplified) grammar Model: elements+=Element+ ; Element: Entity | Test ; Entity: "entity" name=ID ; Test: "test" name=ID "(" ans=NavStatement ")" ; NavStatement returns Statement : '(' NavStatement ')' | {IFElseStatement} 'if' cond=Expr 'then' if=NavStatement (=> 'else' else=NavStatement)? | {URLNavigation} 'url' url=Expr | {BackStatement} 'back' | {RefStatement} '#' uebergang=[Entity|ID] ; enum Expr: YES | NO ; and following dummy example model: entity Uebergang_1 test x ( if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 else if YES then #Uebergang_1 ) the editor hangs up on invocation of content assist at the end of the file Reproducible: Always