#!/usr/bin/perl

use Template::Alloy;
my $ta = Template::Alloy->new;

$ta->_vars->{'func'} = sub { local $" = ', '; "You passed me (@_)" };
$ta->_vars->{'a'}    = 3;
$ta->_vars->{'b'}    = 4;

$ta->define_operator({
    type       => 'left',  # actually associativiy
    precedence => 85,      # same as '+' in $Template::Alloy::OPERATORS table
    symbols    => ['+++'],
    play_sub   => sub { int($_[0]) + int($_[1]) },
});

for my $expr (
    '1 + 2',
    '1 + 2 * 3',
    '(1 + 2) * 3',
    '2.7e+10 * 3.0e-9', # scientific
    'a + b',            # variables
    'func(1 + 2, 3)',   # functions
    '1.2 +++ 3.4 * 2',  # custom ops
    '1 ? 2 : 3',
    'a + (b',
    '3 + 4 foobar',
    ) {
    my $copy = $expr;
    print "--------------------\n";
    print "- expr: $expr\n";
    print "- outp: ".eval{ $ta->play_expr($ta->parse_expr(\$copy)) }."\n";
    if ($@) {
        print "- err : $@\n";
    } else {
        print "- err : Failed to consume entire string\n" if pos $copy != length $expr;
        print "- tree: ".Template::Alloy->dump_parse_expr(\$expr)."\n";
    }
}