Re: [PATCH v1 1/6] docs/match: add pattern matching examples

[Maxime Devos]

On 26-01-2023 19:57, Blake Shaw wrote:
> +A pattern matcher does precisely what the name implies: it matches
> +some arbitrary pattern, and returns some result accordingly.

It doesn't need to return anything -- while functional style is common 
in Guile, imperative is still possible.  It can return multiple things 
with 'values'.  I propose replacing 'result' with 'results'.

>   @example
> -(let ((l '(hello (world))))
> -  (match l           ;; <- the input object
> -    (('hello (who))  ;; <- the pattern
> -     who)))          ;; <- the expression evaluated upon matching
> -@result{} world
> +(define (english-base-ten->number name)
> +  (match name
> +    ('zero   0)
> +    ('one    1)
> +    ('two    2)
> +    ('three  3)
> +    ('four   4)
> +    ('five   5)
> +    ('six    6)
> +    ('seven  7)
> +    ('eight  8)
> +    ('nine   9)))
> +
> +(english-base-ten->number 'six)
> +@result{} 6

This is a suboptimal example; this would be better done with 'case'.
I propose replacing it with another example, or adding a note that one 
would normally use 'case' for this.

Greetings,
Maxime.

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