naming_confusion

scala> def foo!@$# = null
<console>:1: error: '=' expected but identifier found.
       def foo!@$# = null
              ^

scala> def foo_!@$# = null
<console>:1: error: '=' expected but identifier found.
       def foo_!@$# = null
                 ^

scala> def foo_!@_$# = null
<console>:1: error: '=' expected but identifier found.
       def foo_!@_$# = null
                 ^

scala> def foo_!@ = null   
foo_$bang$at: Null

scala> def foo_!@# = null
foo_$bang$at$hash: Null

scala> def foo_!@#$ = null
<console>:1: error: '=' expected but identifier found.
       def foo_!@#$ = null
                  ^

scala> def foo@ = null    
<console>:1: error: '=' expected but '@' found.
       def foo@ = null
              ^

scala> def foo1@ = null
<console>:1: error: '=' expected but '@' found.
       def foo1@ = null
               ^

scala> def foo1_@ = null
foo1_$at: Null

scala> def foo1_@$foo = null
<console>:1: error: '=' expected but identifier found.
       def foo1_@$foo = null
                 ^

scala> def foo1_@_$foo = null
<console>:1: error: '=' expected but identifier found.
       def foo1_@_$foo = null
                 ^

scala> def foo1$foo = null   
foo1$foo: Null

scala> def foo1$1 = null  
foo1$1: Null

scala> def foo_# = null 
foo_$hash: Null

scala> def foo_$# = null
<console>:1: error: '=' expected but '#' found.
       def foo_$# = null
                ^

scala> def foo_$1# = null
<console>:1: error: '=' expected but '#' found.
       def foo_$1# = null
                 ^

scala> def foo_$1_# = null
foo_$1_$hash: Null

scala>