spec: explain function invocation and passing of parameters more precisely

- Describe that function invocation allocates space for a functions'
  variables.
- Explain parameter passing in terms of assignments.

Change-Id: Ia693d73a570f7d1aa2ac05e6095b4e602e4e9bf2
Reviewed-on: https://go-review.googlesource.com/c/go/+/635800
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Bypass: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Reviewed-by: Rob Pike <r@golang.org>

diff --git a/doc/go_spec.html b/doc/go_spec.html
index 282f6cde0c80b31a97c5ef85825eb9cc859f535c..fff489c33ac55cbcbef48849a87df4b06af186bc 100644 (file)
--- a/doc/go_spec.html
+++ b/doc/go_spec.html
@@ -1,6 +1,6 @@
 <!--{
        "Title": "The Go Programming Language Specification",
-       "Subtitle": "Language version go1.24 (Dec 12, 2024)",
+       "Subtitle": "Language version go1.24 (Dec 16, 2024)",
        "Path": "/ref/spec"
 }-->
 
@@ -2819,7 +2819,7 @@ values or variables, or components of other, non-interface types.
 
 <p>
 A type argument <code>T</code><i> satisfies</i> a type constraint <code>C</code>
-if <code>T</code> is an element of the type set defined by <code>C</code>; i.e.,
+if <code>T</code> is an element of the type set defined by <code>C</code>; in other words,
 if <code>T</code> <a href="#Implementing_an_interface">implements</a> <code>C</code>.
 As an exception, a <a href="#Comparison_operators">strictly comparable</a>
 type constraint may also be satisfied by a <a href="#Comparison_operators">comparable</a>
@@ -4229,8 +4229,7 @@ calls <code>f</code> with arguments <code>a1, a2, … an</code>.
 Except for one special case, arguments must be single-valued expressions
 <a href="#Assignability">assignable</a> to the parameter types of
 <code>F</code> and are evaluated before the function is called.
-The type of the expression is the result type
-of <code>F</code>.
+The type of the expression is the result type of <code>F</code>.
 A method invocation is similar but the method itself
 is specified as a selector upon a value of the receiver type for
 the method.
@@ -4251,9 +4250,14 @@ or used as a function value.
 <p>
 In a function call, the function value and arguments are evaluated in
 <a href="#Order_of_evaluation">the usual order</a>.
-After they are evaluated, the parameters of the call are passed by value to the function
+After they are evaluated, new storage is allocated for the function's
+<a href="#Variables">variables</a>, which includes its parameters
+and results.
+Then, the arguments of the call are <i>passed</i> to the function,
+which means that they are <a href="#Assignment_statements">assigned</a>
+to their corresponding function parameters,
 and the called function begins execution.
-The return parameters of the function are passed by value
+The return parameters of the function are passed
 back to the caller when the function returns.
 </p>
 
@@ -4267,9 +4271,9 @@ As a special case, if the return values of a function or method
 <code>g</code> are equal in number and individually
 assignable to the parameters of another function or method
 <code>f</code>, then the call <code>f(g(<i>parameters_of_g</i>))</code>
-will invoke <code>f</code> after binding the return values of
-<code>g</code> to the parameters of <code>f</code> in order.  The call
-of <code>f</code> must contain no parameters other than the call of <code>g</code>,
+will invoke <code>f</code> after passing the return values of
+<code>g</code> to the parameters of <code>f</code> in order.
+The call of <code>f</code> must contain no parameters other than the call of <code>g</code>,
 and <code>g</code> must have at least one return value.
 If <code>f</code> has a final <code>...</code> parameter, it is
 assigned the return values of <code>g</code> that remain after
@@ -4315,7 +4319,7 @@ If <code>f</code> is <a href="#Function_types">variadic</a> with a final
 parameter <code>p</code> of type <code>...T</code>, then within <code>f</code>
 the type of <code>p</code> is equivalent to type <code>[]T</code>.
 If <code>f</code> is invoked with no actual arguments for <code>p</code>,
-the value passed to <code>p</code> is <code>nil</code>.
+the value <a href="#Calls">passed</a> to <code>p</code> is <code>nil</code>.
 Otherwise, the value passed is a new slice
 of type <code>[]T</code> with a new underlying array whose successive elements
 are the actual arguments, which all must be <a href="#Assignability">assignable</a>