how to pass dynamic argument in function

Question

What I am doing

 func foo(a string) {}

 func bar(b, c string)

 type fn func(string)

 m: = map[string] fn {
     "a": "foo",
     "b": "bar"
 }

when I call function like this

  m["a"]("Hello")
  m["b"]("Hello", "World")

I got an error because type fn func(string) here fn have single parameter but I pass double parameter in m["b"]("Hello", "World")

Error : [ cannot use (type func(string, string)) as type fn in map value ]

I want to make dynamic type fn func(string) so that I can pass number of parameter so that I can call like this

  m["a"]("Hello")
  m["b"]("Hello", "World")

What you want to do is _impossible_ in Go: You have to redesign. — Volker, Mar 07 '18 at 10:03
All you can do is use variadic function to take any number of arguments.@Volker is correct — Himanshu, Mar 07 '18 at 10:11
You must come up with a single function type which allows all the use cases. Variadic functions are one solution. Functions taking an interface argument might be an other. — Volker, Mar 07 '18 at 10:23
I am trying to do this with `interface{}` this is right approach — Manjeet Thakur, Mar 07 '18 at 10:24

Himanshu · Answer 1 · 2018-03-08T17:11:40.017

4

Create a variadic function which will take any number of arguments as parameters on passing it to function.

 func foo(nums ...string) {}

 m:= map[string]fn{
     "a": "foo",
     "b": "bar"
 }

For more on variadic functions check this Answer

edited Mar 08 '18 at 17:11

answered Mar 07 '18 at 09:42

Himanshu

No I can't do this because then i need to check inside foo function that how many arguments are coming – Manjeet Thakur Mar 07 '18 at 09:49
you can do that by checking on struct rather than on every function – Himanshu Mar 07 '18 at 09:52

score 1 · Accepted Answer · edited Mar 07 '18 at 20:36

1

Solve using interface

m: = map[string]interface{} {
     "a": "foo",
     "b": "bar"
 }

edited Mar 07 '18 at 20:36

Al Foиce ѫ

answered Mar 07 '18 at 13:03

Manjeet Thakur