-
-
Notifications
You must be signed in to change notification settings - Fork 119
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
Support for functions written in go when used as a library #43
Comments
I'm working on this in #46, and you will be able to define your internal function as follows. Any thoughts? package main
import (
"fmt"
"log"
"github.com/itchyny/gojq"
)
var compilerOptions = []gojq.CompilerOption{
// gojq.WithFunction({function name}, {arity (argument count)}, {function})
gojq.WithFunction("f", 0, func(x interface{}, _ []interface{}) interface{} {
if x, ok := x.(int); ok {
return x * 2
}
return fmt.Errorf("f cannot be applied to: %v", x)
}),
gojq.WithFunction("g", 1, func(x interface{}, xs []interface{}) interface{} {
if x, ok := x.(int); ok {
if y, ok := xs[0].(int); ok {
return x + y
}
}
return fmt.Errorf("g cannot be applied to: %v, %v", x, xs)
}),
}
func main() {
query, err := gojq.Parse(".[] | f | g(3)")
if err != nil {
log.Fatalln(err)
}
code, err := gojq.Compile(query, compilerOptions...)
if err != nil {
log.Fatalln(err)
}
iter := code.Run([]interface{}{1, 2, 3, 4, 5})
for {
v, ok := iter.Next()
if !ok {
break
}
fmt.Printf("%v\n", v)
}
} |
Added some comments in the PR. API looks good to me. |
I do support optional arguments in my hack, but now when i think about it that might be bad and the correct way would be to use multiple |
Rebased and fixed my things on top of your branch, seems to work fine 👍 |
That's exactly what I was concerned. And supporting same function name with different arities introduces a bit hacky code. I'm wondering making the second argument of WithFunction to |
When I give up supporting adding the functions with the same name, the code would be clean. For example, using |
I think in most cases you want min/max arg count range? I guess you don't want to support varargs? Sorry could you clarify what you mean by "Supporting all the f/0 to f/3 is difficult."? hard to do in the gojq implementation or hard to write custom functions that behave well? |
I like the idea of giving both min/max arity. It will cover the use case without duplicating the function implementation with the same name.
I was thinking of overwriting the former definition by the latter when the function name conflicts. But I can implement the case by the same way I used to do within the previous implementation accepting single arity. So user don't need to worry about this (see this test for sample). Thanks for your valuable feedback, I will merge the branch in a few days. |
Nice! glad I can help. And thank you for gojq, very useful and i've learned a lot while reading the code. Did you see my comment about passing along |
Yes, I was to push my changes after writing tests. |
@itchyny 👍 |
@itchyny Thanks! |
Hello! Would it be possible to add support for own "internal" functions written in go when using gojq as a library?
I had a quick look at the code and it seemed not that far away but maybe i'm missing something? If you think it's a good i would even be happy to try implement it if you give some pointers.
The text was updated successfully, but these errors were encountered: