call

call(x, args...)

If x is not a Function, then x(args...) is equivalent to call(x, args...). This means that function-like behavior can be added to any type by defining new call methods.

Examples

Call a function with arguments:
```
julia> function add_numbers(a, b)
          return a + b
      end
julia> call(add_numbers, 5, 3)
8
```
In this example, the call function is used to invoke the add_numbers function with arguments 5 and 3. It returns the sum of the two numbers.
Call a function-like object:
```
julia> struct MultiplyByTwo
          value::Int
      end

julia> (m::MultiplyByTwo)(x) = m.value * x

julia> m = MultiplyByTwo(5)
julia> call(m, 3)
15
```
Here, the call function is used to invoke the function-like behavior of the MultiplyByTwo object. The call method defined for MultiplyByTwo multiplies the object's value field with the argument x.
Handle non-function objects:
```
julia> x = 10
julia> call(x, "Hello, world!")
ERROR: MethodError: objects of type Int64 are not callable
```
If the provided x is not a function or a function-like object, an error will be thrown. In this example, calling call with an integer x results in a MethodError because integers are not callable.

Common mistake example:

julia> call(5, 3)
ERROR: MethodError: objects of type Int64 are not callable

In this example, the mistake is passing an integer 5 as the first argument to call. Since integers are not callable, a MethodError is thrown. Make sure to pass a callable object or a function as the first argument to call.

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call

Examples

See Also

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