That still may be of little help in, say, a perl IDE, as the meaning of a program _can_ depend on the input it reads.
"But that will not happen in practice"
If you think that to be the case, use a language that _can_ be parsed. That makes life easier for implementers of IDE's, refactoring tools, etc. and costs you nothing (given the "that will not happen in practice" claim)
"But that will not happen in practice"
If you think that to be the case, use a language that _can_ be parsed. That makes life easier for implementers of IDE's, refactoring tools, etc. and costs you nothing (given the "that will not happen in practice" claim)