Re^3: Parsing Problems

[haj]

Two things stand out here:

• $ARGV[2] might contain un-decoded UTF-8 characters in "modern" terminals. File systems with UTF-8 characters behave differently, depending on the platform (Windows/Unix).
• (/$line) looks weird. That needs really special values for $line to produce valid Perl!

An idea is to print the string you're evaling, and of course checking whether eval produced an error in $@:

my $code = qq~modes::~ . $ARGV[2] . qq~::flex(/$line);~;
warn $code;
eval $code;
warn "Eval failed: '$@'" if $@;

[ftherese]

Okay! Now we're getting somewhere. In the old environment, no error is reported. In the new environment: Undefined subroutine &modes::three::a called at (eval 32) line 1. ...
Also, I mistyped because I'm on my phone it is \$line.