add :allow-blank, validate-all

[vindarel]

WDYT?

It's shorter than "||" and "&&". It seems to be working OK.

(clavier::validate-all (list  :ALLOW-BLANK (clavier:len :min 3) (clavier:len :min 4)) "a")
NIL
("Length of \"a\" is less than 3" "Length of \"a\" is less than 4")


(clavier::validate-all (list  :ALLOW-BLANK (clavier:len :min 3) (clavier:len :min 4)) "")
T
NIL

for #7

[mmontone]

My problem with this is that I think validate-all is equivalent to a generalized and (make the and-validator work with several arguments instead of two). is it not? Also for or-validator . I would accept a pull request for that.

I prefer not having the validate-all and the keyword syntax so as to maintain simplicity and consistency (in my view).

[mmontone]

Remember you can have that validate-all function as part of your project, outside of clavier . So you can still have your cake if you want that, for your project, despite my rejection.

I mention this because sometimes we forget we can do things from the outside.

[vindarel]

I plan to expose this api to end-users (developers). They define a list of validators for their form fields. So for me it's going to be required to have a simpler syntax than

|| (blank) 
    && (len)

for such a common need. I prefer them to write

(list :allow-blank (len))

I want field declarations to be as simple as in Django.

Also, it is quite logical to validate many validators, isn't it? (and "validator-collection" isn't simple?) My app already had to add the validate-all function (again, for an HTML form).

I mention this because sometimes we forget we can do things from the outside.

yes, quite the contrary, often a lisper cooks his own food, it's too simple to not contribute!! ;)

I'll think through the needs more.

---

is it not?

I have to check… :allow-blank kind of does a early exit, I don't think the and validator allows that?

[mmontone]

I plan to expose this api to end-users (developers). They define a list of validators for their form fields. So for me it's going to be required to have a simpler syntax than

|| (blank) 
    && (len)

for such a common need. I prefer them to write

(list :allow-blank (len))

I want field declarations to be as simple as in Django.

Ok. But I see that as part of your project. I prefer Clavier to only give you the building blocks in a consistent way.

Also, it is quite logical to validate many validators, isn't it? (and "validator-collection" isn't simple?) My app already had to add the validate-all function (again, for an HTML form).

Yes. But my point is "validate many validators" is equivalent to an and validators with all the many validators.

I mention this because sometimes we forget we can do things from the outside.

yes, quite the contrary, often a lisper cooks his own food, it's too simple to not contribute!! ;)

I'll think through the needs more.

is it not?

I have to check… :allow-blank kind of does a early exit, I don't think the and validator allows that?

It does not. My point was about "validate many validators" being equivalent to an and validator. Again, I see :allow-blank as part of your project "syntax".

[mmontone]

Ok. I see your point of validate-all combined with the early exit of :allow-blank . But I still prefer not to have it in Clavier.

[vindarel]

Understood, and so be it. I wanted to extract that feature from my app, but I'm not happy with a fork or a trivial library. Let's see…