about adding function `update-if`

[Hiroyuki Fudaba]

Hi all,

I often get in a situation when I need to update a value in hashmap if it satisfies a predicate, e.g.

```

(def p {:name "James" :age 26})

(update p :age #(if (< % 30) (inc %) %))

```

Wouldn't it be nice if we had a function `update-if` in core as we already have ?

Then we can rewrite the code as following:

```

(update-if p :age #(< % 30) inc)

```

Any comments or suggestions are welcome!

Thanks,

Hiroyuki Fudaba

[Sean Corfield]

On 8/15/16, 6:40 AM, "Hiroyuki Fudaba" <cloju...@googlegroups.com on behalf of deli...@gmail.com> wrote:

(def p {:name "James" :age 26})
(update p :age #(if (< % 30) (inc %) %))

What I tend to do in situations like that is use cond->

(update p :age #(cond-> % (< % 30) inc))

We also have an in-house version that threads the condition as well:

(update p :age #(condp-> % (< 30) inc))

Sean Corfield -- (904) 302-SEAN -- (970) FOR-SEAN
An Architect's View -- http://corfield.org/

"Perfection is the enemy of the good."
-- Gustave Flaubert, French realist novelist (1821-1880)