1. now it's moved to S06-operator-overloading/infix.t
2. note that default Left-associative works, this ticket in fact about
reserved words. See the example below:
```
{
my sub infix:<Z> ($a, $b) {
$a ** $b;
}
is (2 Z 1 Z 2), 4, "default Left-associative works.";
}
# Calling infix:<Z>(Int, Int, Int) will never work with declared signature
($a, $b)
```
```
{
my sub infix:<B> ($a, $b) {
$a ** $b;
}
is (2 B 1 B 2), 4, "default Left-associative works.";
}
# ok
```
```
{
my sub infix:<.> ($a, $b) {
$a ** $b;
}
is (2 . 1 . 2), 4, "default Left-associative works.";
}
# Unsupported use of . to concatenate strings; in Perl 6 please use ~
```
```
{
my sub infix:<~> ($a, $b) {
$a ** $b;
}
is (2 ~ 1 ~ 2), 4, "default Left-associative works.";
}
# ok
```
```
{
my sub infix:<@> ($a, $b) {
$a ** $b;
}
is (2 @ 1 @2), 4, "default Left-associative works.";
}
# ok
```
