test_constraint( $type, $tests, [ $describer ] )

The third argument is optional. This is a sub reference which will be called to generate a description of the value being tested. This defaults to calling this package's "describe" sub, but you can provide your own.

describe($value)

builtins_tests( $GLOB, $GLOB_OVERLOAD, $GLOB_OVERLOAD_FH )

  {
      Bool => {
          accept => [
              $ZERO,
              $ONE,
              $BOOL_OVERLOAD_TRUE,
              $BOOL_OVERLOAD_FALSE,
              ...,
          ],
          reject => [
              $INT,
              $NEG_INT,
              $NUM,
              $NEG_NUM,
              ...,
              $OBJECT,
          ],
      },
      Maybe => {...},
  }

You need to pass in a glob, an object which overloads globification, and an object which overloads globification to return an open filehandle. See below for more details on how to create these things.

Variables

• $ZERO
• $ONE
• $INT

  An arbitrary positive integer.

• $NEG_INT

  An arbitrary negative integer.

• $NUM

  An arbitrary positive non-integer number.

• $NEG_NUM

  An arbitrary negative non-integer number.

• $EMPTY_STRING
• $STRING

  An arbitrary non-empty string.

• $NUM_IN_STRING

  An arbitrary string which contains a number.

• $INT_WITH_NL1

  An string containing an integer followed by a newline.

• $INT_WITH_NL2

  An string containing a newline followed by an integer.

• $SCALAR_REF
• $SCALAR_REF_REF

  A reference containing a reference to a scalar.

• $ARRAY_REF
• $HASH_REF
• $CODE_REF
• $GLOB_REF
• $FH

  An opened filehandle.

• $FH_OBJECT

  An opened IO::File object.

• $REGEX

  A regex created with "qr//".

• $REGEX_OBJ

  A regex created with "qr//" that was then blessed into class.

• $FAKE_REGEX

  A non-regex blessed into the "Regexp" class which Perl uses internally for "qr//" objects.

• $OBJECT

  An arbitrary object.

• $UNDEF
• $CLASS_NAME

  A string containing a loaded package name.

• $BOOL_OVERLOAD_TRUE

  An object which overloads boolification to return true.

• $BOOL_OVERLOAD_FALSE

  An object which overloads boolification to return false.

• $STR_OVERLOAD_EMPTY

  An object which overloads stringification to return an empty string.

• $STR_OVERLOAD_FULL

  An object which overloads stringification to return a non-empty string.

• $STR_OVERLOAD_CLASS_NAME

  An object which overloads stringification to return a loaded package name.

• $NUM_OVERLOAD_ZERO
• $NUM_OVERLOAD_ONE
• $NUM_OVERLOAD_NEG
• $NUM_OVERLOAD_DECIMAL
• $NUM_OVERLOAD_NEG_DECIMAL
• $CODE_OVERLOAD
• $SCALAR_OVERLOAD

  An object which overloads scalar dereferencing to return a non-empty string.

• $ARRAY_OVERLOAD

  An object which overloads array dereferencing to return a non-empty array.

• $HASH_OVERLOAD

  An object which overloads hash dereferencing to return a non-empty hash.

Globs and the _T::GlobOverload package

  my $GLOB = do {
      no warnings 'once';
      *SOME_GLOB;
  };

The "_T::GlobOverload" package is defined when you load "Test::Specio" so you can create your own glob overloading objects. Such objects cannot be exported because the glob they return does not transfer across packages properly.

You can create such a variable like this:

  local *FOO;
  my $GLOB_OVERLOAD = _T::GlobOverload->new( \*FOO );

If you want to create a glob overloading object that returns a filehandle, do this:

  local *BAR;
  open BAR, '<', $^X or die "Could not open $^X for the test";
  my $GLOB_OVERLOAD_FH = _T::GlobOverload->new( \*BAR );