From 382143abd871d9b2c73df08ffd2928c44f314ab3 Mon Sep 17 00:00:00 2001 From: Benjamin Herr Date: Sat, 2 Mar 2013 01:07:01 +0100 Subject: [PATCH] doc/rust.md: Demonstrate the `f::()` syntax more often The "Generic functions" subsection mentions that generic functions are instantiated based on context, so let's also mention right away (with a link to the #paths section) that an explicit form is available. This also adds an example to the function call expression section that explicitly instantiates a generic function. --- doc/rust.md | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/doc/rust.md b/doc/rust.md index 13d897a00d2f1..862358859e5c4 100644 --- a/doc/rust.md +++ b/doc/rust.md @@ -908,6 +908,11 @@ function defined above on `[1, 2]` will instantiate type parameter `T` with `int`, and require the closure parameter to have type `fn(int)`. +The type parameters can also be explicitly supplied in a trailing +[path](#paths) component after the function name. This might be necessary +if there is not sufficient context to determine the type parameters. For +example, `sys::size_of::() == 4`. + Since a parameter type is opaque to the generic function, the set of operations that can be performed on it is limited. Values of parameter type can always be moved, but they can only be copied when the @@ -2040,12 +2045,14 @@ an optional reference slot to serve as the function's output, bound to the `lval` on the right hand side of the call. If the function eventually returns, then the expression completes. -An example of a call expression: +Some examples of call expressions: ~~~~ # fn add(x: int, y: int) -> int { 0 } +# use core::from_str::FromStr::from_str; let x: int = add(1, 2); +let pi = from_str::("3.14"); ~~~~ ### Lambda expressions