Spaces after parentheses (GNU Algol 68 Coding Guidelines)

### 2.3 Spaces after parentheses ¶

When writing routine texts always place a space between the formal parameters pack and the mode of the value yielded by the routine.

When writing operator and procedure declarators do not put a space between the parameter modes pack and the mode of the yielded value.

Also in declarers, do not put a space after `op` or `proc` and the parameter modes pack.

    { Space after formal parameters pack in routine text }
    json_foreach_elem(a, (ref JSON_Val v) void: len +:= 1)

    { No space after parameters pack in procedure and operator
      declarators }
    proc(string)void error;