As you asked about syntax checking and not security, I'll assume that you have the security aspect covered.

There's probably a gotcha I haven't thought about, but if you issue a return immediately at the front of the code to be checked, that will prevent any furthur code being executed--except of course for BEGIN{...} and END{...} blocks, see later--but still allow syntax checking to occur.

I believe (quite possibly wrongly), that if you remove any newlines, that BEGIN and END blocks can be match with a regex of /(?:BEGIN|END)\s*\{/ Using this to prefix them with something like sub syntax_check_ will prevent them from being run, but will allow them to also be syntax checked. 

#! perl -slw
use strict;

while(<DATA>) {
    chomp;
    my $code = $_;
    tr/\n//d;
    s[((?:BEGIN|END)\s*{)][sub syntax_check_$1]g;
    eval 'return;' . $_;
    print "'$code' \n\t: ", $@ ? "Fails with\n$@" : 'Passes syntax che
+ck';
}
__END__
INIT { print '*** GOTCHA!!! ***'; }
BEGIN{ print '*** GOTCHA!!! ***'; }
END  { print '*** GOTCHA!!! ***'; }
my $a = 1;
my $a = cool;
my $

[download]

Whether this level of syntax checking is enough to satisfy your requirements only you will know.

Examine what is said, not who speaks.

The 7th Rule of perl club is -- pearl clubs are easily damaged. Use a diamond club instead.

In reply to Re: run-time syntax checking by BrowserUk
in thread run-time syntax checking by Pardus

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