Edit documentation.

doc/src/language/loop.md

@@ -3,6 +3,11 @@ Infinite `loop`
 
 {{#include ../links.md}}
 
+Infinite loops follow C syntax.
+
+Like C, `continue` can be used to skip to the next iteration, by-passing all following statements;
+`break` can be used to break out of the loop unconditionally.
+
 ```rust
 let x = 10;
 
@@ -13,3 +18,6 @@ loop {
     if x == 0 { break; }    // break out of loop
 }
 ```
+
+Beware: a `loop` statement without a `break` statement inside its loop block is infinite -
+there is no way for the loop to stop iterating.