Validate an empty argument list

[clueless-newbie]

Calling a sub that doesn't take arguments with arguments is something gone wrong. Currently validation_for doesn't have a means for saying this sub doesn't take any arguments --- making it necessary to "die q{This sub doesn't take arguments.} if (@_);". If one is using validation_for elsewhere it would be nice to use it in this case too.

[autarch]

So something like this?

my $validator = validation_for(none => 1)

That would be pretty easy to add. Are you interested in writing a PR?

[clueless-newbie]

My apologies, sir for being so clueless. I was thinking of something like this: validation_for( params => [] ) or validation_for( params => {} } or validation_for() the last might be as simple as (none => 1). I'm clueless about github and only beg for a change in the interest of being consistent in my coding.

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On Mon, Jan 19, 2026 at 4:15 AM Dave Rolsky ***@***.***> wrote: *autarch* left a comment (houseabsolute/Params-ValidationCompiler#28) <#28 (comment)> So something like this? my $validator = validation_for(none => 1) That would be pretty easy to add. Are you interested in writing a PR? — Reply to this email directly, view it on GitHub <#28 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABAHLVZYY5VTA3WCBS3X7JD4HSOBZAVCNFSM6AAAAACSDRQUDGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTONRXGI2TKOJXHE> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[autarch]

If we wanted to use the params key I'd want it to be some sort of sentinel value exported by this module, so you could do params => $NONE. Otherwise, how can we distinguish an empty params key (which is probably a bug) from actually wanting to specify no parameters.

[clueless-newbie]

If validation_for(params=>$NONE) works for you --- it will work for me. (Sorry if I'm paranoid but having called my own routines with the wrong number of parameters and all those other blessings from St. Murphy, I'm concluding better to be safe than sorry.)

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On Sat, Jan 24, 2026 at 2:38 AM Dave Rolsky ***@***.***> wrote: *autarch* left a comment (houseabsolute/Params-ValidationCompiler#28) <#28 (comment)> If we wanted to use the params key I'd want it to be some sort of sentinel value exported by this module, so you could do params => $NONE. Otherwise, how can we distinguish an empty params key (which is probably a bug) from actually wanting to specify no parameters. — Reply to this email directly, view it on GitHub <#28 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABAHLVYNABMTSQO7VNCXDWD4IMOOZAVCNFSM6AAAAACSDRQUDGVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTOOJUGA4TIOBZGA> . You are receiving this because you authored the thread.Message ID: ***@***.***>