Re^2: how to check syntax of code inside a scalar?

Uggh, it's a bit shortsighted that there's no built-in function for this. However, after playing a bit, I've found that this can be simulated without having to actually execute the scalar's contents by pre-pending "return;" and testing with eval:

sub syntax_ok {
        my $source = "return;\n" . shift;
        eval $source;
        return 1 unless $@;
        return 0;
}
[download]

Thanks!

Comment on Re^2: how to check syntax of code inside a scalar? Download Code

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Re^3: how to check syntax of code inside a scalar? by Crackers2 (Parson) on Aug 04, 2010 at 21:04 UTC
Bad idea... try it with this: `syntax_ok(qq{BEGIN { print "yay\n"; }});` [download] and you'll see that the BEGIN block still gets run, bypassing your `return` statement. So I'd consider it rather unsafe.	[reply] [d/l] [select]
Re^4: how to check syntax of code inside a scalar? by snoopy (Curate) on Aug 04, 2010 at 21:55 UTC
This does however seem to match the `perl -c` syntax check. From perlrun: -c causes Perl to check the syntax of the program and then exit without executing it. Actually, it will execute "BEGIN", "UNITCHECK", "CHECK", and "use" blocks, because these are considered as occurring outside the execution of your program. "INIT" and "END" blocks, however, will be skipped. `perl -c -e 'BEGIN { print "yay\n"; }; print "boo\n"'` [download] `yay -e syntax OK` [download]	[reply] [d/l] [select]
Re^5: how to check syntax of code inside a scalar? by aquarium (Curate) on Aug 05, 2010 at 03:39 UTC
What if you always inject a `BEGIN {exit}` [download] will it still do the compile step? the hardest line to type correctly is: stty erase ^H	[reply] [d/l]
Re^6: how to check syntax of code inside a scalar? by snoopy (Curate) on Aug 05, 2010 at 05:05 UTC


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