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Postings from June 2022
2022-6-15 16:21 Alexander Hartmaier <alex.hartmaier@gmail.com> wrote:
> On Tue, Jun 14, 2022 at 7:10 PM Tom Molesworth <tom@deriv.com> wrote:
>
>> On Wed, 15 Jun 2022 at 00:13, Graham Knop <haarg@haarg.org> wrote:
>>
>>> On Tue, Jun 14, 2022 at 6:02 PM Alexander Hartmaier
>>> <alex.hartmaier@gmail.com> wrote:
>>> >
>>> > On Tue, Jun 14, 2022 at 11:33 AM Graham Knop <haarg@haarg.org> wrote:
>>> >>
>>> >> On Tue, Jun 14, 2022 at 8:15 AM Alexander Hartmaier
>>> >> <alex.hartmaier@gmail.com> wrote:
>>> >> > Look at some of the other modules using the return value of require
>>> from the grep.metacpan.org link.
>>> >>
>>> >> Do you have a concrete example?
>>>
>>
>> There are plenty of cases which are effectively "`require` is used
>> instead of `do`", i.e. calling `require` and the subsequent code relies on
>> the data, rather than truth of the return value.
>>
>> Some examples from just the first page of results - there are others on
>> that page:
>>
>> https://grep.metacpan.org/search?qci=&q=%3D%20require&qft=&qd=AWS-Lambda
>>
>> my $app = require "$ENV{'LAMBDA_TASK_ROOT'}/app.psgi";
>> my $func = AWS::Lambda::PSGI->wrap($app);
>>
>> https://grep.metacpan.org/search?qci=&q=%3D%20require&qft=&qd=App-Alice
>>
>> my $config = {};
>> if (-e $self->fullpath) {
>> $config = require $self->fullpath;
>>
>> https://grep.metacpan.org/search?qci=&q=%3D%20require&qft=&qd=App-Chart
>>
>> my $aref = require App::Chart::Gtk2::IndicatorModelGenerated;
>>
>> All of these are somewhat fragile: call the code twice or have something
>> else `require` the relevant module/file first, and they'd have problems.
>> However, given how often this pattern appears,
>> require-returns-`builtin::true` may be too disruptive if strictly enforced?
>>
>> Keeping the original value _also_ doesn't seem like a good idea, `package
>> Example; my $should_drop_out_of_scope = ...;` for example.
>>
>> I saw those but they confused me.
> So require just returns what the loaded file returns? So in case the file
> ends in 1;, the return value is 1, but some return a blessed object and
> this is returned?
>
> Is that a feature or a misuse of 'require'?
>
I also want to know either of the following.
1. "require" ignores the return value of the .pm file to check whether it
is successful, and "require" returns builtin::true.
2. "require" ignores the return value of the .pm file to check whether it
is successful, and "require" returns the return value of the .pm file.
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