prevent stringification for hash-keys

morgon has asked for the wisdom of the Perl Monks concerning the following question:

Hi,

Sorry for being too lazy to read the documentation, I am sure I would find my answer here...

But I just spend 15 minutes (or more) on a bug where I wrote

if($hash{key}) {
[download]

where I should have written

if($hash{$key}) {
[download]

so my problem is the automatic stringification of hash-keys that prevents such a but to be discovered at compile-time.

Plenty of times this is exactly what I want, but sometimes (as here) it can conceal bugs - so is there a way to turn it off, so that accessing a hash-element via bareword would be a compiliation error?

I am sure there is...

Many thanks!

Comment on prevent stringification for hash-keys Select or Download Code

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Re: prevent stringification for hash-keys by tobyink (Canon) on Feb 17, 2019 at 01:11 UTC
Perl::Critic::Policy::CodeLayout::ProhibitHashBarewords toby döt ink	[reply]
Re^2: prevent stringification for hash-keys by 1nickt (Canon) on Feb 17, 2019 at 03:22 UTC
Heheh yes tobyink I thought about that too, but the OP appears to want to forbid in code the use of a string as a hash key, whether quoted or not, and only allow using a declared variable. IIUC. The way forward always starts with a minimal test.	[reply]
Re^3: prevent stringification for hash-keys by soonix (Canon) on Feb 17, 2019 at 07:27 UTC
No, he wants to avoid stringification of hash keys, especially of barewords.	[reply]
Re^4: prevent stringification for hash-keys by 1nickt (Canon) on Feb 17, 2019 at 12:37 UTC
Re^5: prevent stringification for hash-keys by soonix (Canon) on Feb 17, 2019 at 23:57 UTC
Re: prevent stringification for hash-keys by 1nickt (Canon) on Feb 16, 2019 at 23:47 UTC
See the core module Hash::Util. `use strict; use warnings; use Hash::Util 'lock_keys'; my $key = 'foo'; lock_keys my %hash, ($key, 'bar'); $hash{$key}++; $hash{'key'}++; __END__` [download] `$ perl 1230007.pl Attempt to access disallowed key 'key' in a restricted hash at 1230007 +.pl line 11.` [download] Hope this helps! The way forward always starts with a minimal test.	[reply] [d/l] [select]
Re^2: prevent stringification for hash-keys by morgon (Priest) on Feb 16, 2019 at 23:52 UTC
That's sort of a solution, but I still would need to explicitely call lock_keys on every hash I use. What I really want is a way to make `$hash{bare_word}` a compile-time error in a lexical scope...	[reply] [d/l]


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