zl:1 - FTP

471
selectq-every
(let «x 'Bird»
(zl:selectq x
(foo (do-this»
(bar (do-that»
«baz quux mum) (do-the-other-thing»
(otherwise (zl:ferror nil "Hey there, never heard of -5" x»»
=> Error: Hey there, never heard of BIRO
is equivalent to:
(let «x 'Bird»
(cond «eq x 'foo) (do-this»
«eq x 'bar) (do-that»
«zl:memq x '(baz quux mum» (do-the-other-thing»
(t (zl:ferror nil "Hey there, never heard of -5" x»»
=> Error: Hey there, never heard of BIRO
For a table of related items: See the section "Conditional Functions" in
Symbolics Common Lisp: Language Concepts.
I
selectq-every obj &body clauses Special Form
A 'conditional that chooses one of its clauses to execute by comparing the
value of a form against various constants, which are typically keyword sym- ",
boIs. I ts form is as follows:
(sel ectq-every key-form
(test consequent consequent ... )
(test consequent consequent ... )
(test consequent consequent ... )
... )
The Irrst thing selectq-every does is to evaluate key-form; call the resulting
value key. Then selectq-every considers each of the clauses in turn.
If key matches the clause's test, the consequents of this clause are
evaluated, and selectq-every returns the value of the last consequent. If
there are no matches, selectq-every returns nil.
A test can be any of the following:
A symbol
A number
A list
t or otherwise
If the key is eq to the symbol, it matches.
If the key is eq to the number, it matches. Only small
numbers (integers) work.
If the key is eq to one of the elements of the list, then it
matches. The elements of the list should be symbols or
integers.
The symbols t and otherwise are special keywords that
match anything. Either symbol can be used; t is mainly