--- On Mon, 4/1/10, yary <[email protected]> wrote:
> From: yary <[email protected]>
> How about
> multi sub foo(Any $name) { die "Houston, we have a major
> malfunction."}
Looks like tha would work, but it forces the developer to remember to write
this extra code every time they may have a constraint failure, if they forget,
we're back to the old, cryptic message. It would be much nicer to be able to
do this (psuedo-code, obviouly):
subset Filename of Str where { $_ ~~ :f }
:OnFail { "No such file: '$_'" }
subset Celsius of Num where { $_ >= -273.15 }
:OnFail { "Celsius temperature should be a Num >= -273.15, not '$_' " }
With something akin to that, developers won't have to write extra boilerplate
every time a constraint fails. Plus, the code is friendlier :)
Cheers,
Ovid
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