diff options
Diffstat (limited to 'src/rustc')
| -rw-r--r-- | src/rustc/middle/kind.rs | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/src/rustc/middle/kind.rs b/src/rustc/middle/kind.rs index e6facc2f7fd..0b2df1f94c3 100644 --- a/src/rustc/middle/kind.rs +++ b/src/rustc/middle/kind.rs @@ -9,15 +9,28 @@ import util::ppaux::{ty_to_str, tys_to_str}; import syntax::print::pprust::expr_to_str; import freevars::freevar_entry; -// Kind analysis pass. There are three kinds: +// Kind analysis pass. // -// sendable: scalar types, and unique types containing only sendable types -// copyable: boxes, closures, and uniques containing copyable types -// noncopyable: resources, or unique types containing resources +// There are several kinds defined by various operations. The most restrictive +// kind is noncopyable. The noncopyable kind can be extended with any number +// of the following attributes. +// +// send: Things that can be sent on channels or included in spawned closures. +// copy: Things that can be copied. +// const: Things thare are deeply immutable. They are guaranteed never to +// change, and can be safely shared without copying between tasks. +// +// Send includes scalar types, resources and unique types containing only +// sendable types. +// +// Copy includes boxes, closure and unique types containing copyable types. +// +// Const include scalar types, things without non-const fields, and pointers +// to const things. // // This pass ensures that type parameters are only instantiated with types // whose kinds are equal or less general than the way the type parameter was -// annotated (with the `send` or `copy` keyword). +// annotated (with the `send`, `copy` or `const` keyword). // // It also verifies that noncopyable kinds are not copied. Sendability is not // applied, since none of our language primitives send. Instead, the sending |