#!/usr/bin/env perl

use strict;
use warnings;

use constant {
    NUM => 0,
    EXP => 1,
};

use Test::More;

my @tests = (
    [1, 1],
    [0, 1],
    ['NaN', 0],
    ['Infinity', 0],
    ['-123.', 0],
    ['-123. ', 0],
    ['-123.0', 1],
    ['-123 ', 0],
    ['000', 0],
    ['007', 0],
);

plan tests => 0+@tests;

my $re = qr{(?x:
    ^           # anchor at start
    [+-]?       # optional leading sign
    [0-9]+      # 1 or more ASCII digits
    (?:
        \.      # literal decimal place
        [0-9]+  # 1 or more ASCII digits
    |           # OR
                # nothing
    )
    $           # anchor end
)};

for my $test (@tests) {
    is $test->[NUM] =~ /$re/, !!$test->[EXP],
        "Test that '$test->[NUM]' is "
        . ($test->[EXP] ? 'VALID' : 'INVALID');
}