Spaces in brief clause forms (GNU Algol 68 Coding Guidelines)

### 2.9 Spaces in brief clause forms ¶

It is generally a good idea to have spaces around `|` and `|:` within the brief forms of conditional clauses, case clauses and conformity clauses.

When the brief forms are very short and the units are number denotations, it may be more clear to not use spaces, especially when the form is an operand in a formula.

Examples:

    { Space around | and |: in brief forms }
    (v | (void): "empty", (bool b): (b | "true" | "false"))

    { No spaces may be more readable sometimes }
    int n = 2 + (c>3|10|20);