Undefined #var use causes perl error message without location

[pauloscustodio]

When #var is used and $Var{var} is not defined, the perl issues the error message:
Use of uninitialized value $Var{"var"} in concatenation (.) or string at (eval 10) line 1.
Use of uninitialized value in concatenation (.) or string at (eval 10) line 1.

The error message should tell the input source file line.

[pauloscustodio]

In version 2.10_01, #VAR is expanded to #VAR if no variable named #VAR is defined.
As almost any symbol can be used in a variable name, there is no safe way to extract the variable name from the input, e.g. #VAR may be #V, #VA or #VAR.