=encoding utf-8
=head1 NAME
Call::Context - Sanity-check calling context
=head1 SYNOPSIS
use Call::Context;
sub gives_a_list {
#Will die() if the context is not list.
Call::Context::must_be_list();
return (1, 2, 3);
}
gives_a_list(); #die()s: incorrect context (void)
my $v = gives_a_list(); #die()s: incorrect context (scalar)
my @list = gives_a_list(); #lives
=head1 DISCUSSION
If your function only expects to return a list, then a call in some other
context is, by definition, an error. The problem is that, depending on how
the function is written, it may actually do something expected in testing, but
then in production act differently.
=head1 FUNCTIONS
=head2 must_be_list()
C<die()>s if the calling function is itself called outside list context.
(See the SYNOPSIS for examples.)
=head1 EXCEPTIONS
This module throws instances of C<Call::Context::X>. C<Call::Context::X> is
overloaded to stringify; however, to keep memory usage low, C<overload> is not
loaded until instantiation.
=head1 REPOSITORY
https://github.com/FGasper/p5-Call-Context