id,summary,reporter,owner,description,type,status,priority,milestone,component,version,resolution,keywords,cc,os,architecture,failure,difficulty,testcase,blockedby,blocking,related
1544,Derived Read instances for recursive datatypes with infix constructors are too inefficient,jcpetruzza@…,,"Consider this definition:
{{{
data Exp = C | Exp :+: Exp | Exp :-: Exp deriving ( Read, Show )
}}}
Now, try something like:
{{{
> read ""((((((((((C))))))))))"" :: Exp
}}}
Even this simple expression may take several seconds to parse. It gets worse if you keep adding parenthesis. And even worse if you add more infix constructors....",bug,new,normal,7.6.2,Compiler,6.6.1,,,koen@… doaitse@… malcolm@… emlempsi@…,Unknown/Multiple,Unknown/Multiple,Other,Unknown,,,,