How to Pass Multiple Return Values as Arguments to Functions in Go?

Return Values as Arguments to Multi-Argument Functions

When dealing with functions that return multiple values, it's possible to use these values as input arguments to other functions. However, certain limitations apply when the receiving function has additional parameters.

Consider the following code:

<code class="go">func returnIntAndString() (i int, s string) {...}

func doSomething(msg string, i int, s string) {...}</code>

If we attempt to pass the return values of returnIntAndString() to doSomething() directly:

<code class="go">doSomething("message", returnIntAndString())</code>

Go will complain with the errors:

multiple-value returnIntAndString() in single-value context
not enough arguments in call to doSomething()

This is because Go only allows passing a single value as an argument to a function, even if the return value of the previous function yields multiple values.

To resolve this issue, you have two options:

1. Assign Return Values:
   Assign the return values to temporary variables and pass them individually to doSomething().

   <code class="go">i, s := returnIntAndString()
   doSomething("message", i, s)</code>

2. Return Specific Values:
   In the returnIntAndString() function, return a named struct with fields for each value. Then, pass the struct to doSomething().

   <code class="go">type Result struct {
      I int
      S string
   }
   
   func returnIntAndString() Result {...}
   
   res := returnIntAndString()
   doSomething("message", res.I, res.S)</code>

Remember, Go's specific rules do not allow additional parameters alongside a multi-value return value function when assigning arguments. If the specific conditions outlined in the language specification are not met, you must employ one of the provided solutions.

The above is the detailed content of How to Pass Multiple Return Values as Arguments to Functions in Go?. For more information, please follow other related articles on the PHP Chinese website!