On Monday, June 10, 2013 10:20:20 PM UTC+2, Steven Degutis wrote:
> Sometimes I've wanted a function that takes a value and a bunch of tests,
> and returns it if it passes every test, otherwise nil.
>
> Does this seem useful enough to put into core?
>
>
A simpler variant already exists in core,
On Mon, Jun 10, 2013 at 6:55 PM, Cedric Greevey wrote:
> Hmmm? Maybe
>
> (defn if-and [x & tests]
> (if (every? true? (map #(% x) tests)) x))
>
> for a version that's a function, would short-circuit but for seq chunking,
> and returns nil or x.
>
Yes, that's why you might as well use this:
u
Hmmm? Maybe
(defn if-and [x & tests]
(if (every? true? (map #(% x) tests)) x))
for a version that's a function, would short-circuit but for seq chunking,
and returns nil or x.
Incidentally, I think you can dechunk any seq with (map first (take-while
seq (iterate next s))), but haven't tested t
you can just use (every? true? '(arg1 arg2 )) or def a simple function
.
i think the Core is powerful enough.
2013/6/11 Cedric Greevey
> There's also the defmacro route:
>
> (defmacro if-and [test-expr binding & tests]
> `(let [~binding ~test-expr]
> (and ~@(concat tests [binding])))
There's also the defmacro route:
(defmacro if-and [test-expr binding & tests]
`(let [~binding ~test-expr]
(and ~@(concat tests [binding]
Evaluates test-expr, then evaluates to the result of that if the tests all
pass, and to a falsey value otherwise (in fact, the first falsey value
ret
On Mon, Jun 10, 2013 at 1:20 PM, Steven Degutis wrote:
> Sometimes I've wanted a function that takes a value and a bunch of tests,
> and returns it if it passes every test, otherwise nil.
>
> So I wrote if-and:
>
> (if-and "foo"
>
> string?
> #(.startsWith % "f")
> #(.cont
Sometimes I've wanted a function that takes a value and a bunch of tests,
and returns it if it passes every test, otherwise nil.
So I wrote if-and:
(if-and "foo"
string?
#(.startsWith % "f")
#(.contains % "oo"))
;; => "foo"
(if-and "foo"
string?
#(.start
