manual: note overloading and traits for comparison ops.

This commit is contained in:
Graydon Hoare 2012-10-11 14:17:54 -07:00
parent eff4a36b3e
commit 1d47c0a830

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@ -1697,7 +1697,7 @@ The default meaning of the operators on standard types is given here.
#### Bitwise operators
Bitwise operators apply are, like the [arithmetic operators](#arithmetic-operators),
Bitwise operators are, like the [arithmetic operators](#arithmetic-operators),
syntactic sugar for calls to built-in traits.
This means that bitwise operators can be overridden for user-defined types.
The default meaning of the operators on standard types is given here.
@ -1730,21 +1730,31 @@ and `&&` only when it evaluates to `true`.
#### Comparison operators
Comparison operators are, like the [arithmetic operators](#arithmetic-operators),
and [bitwise operators](#bitwise-operators),
syntactic sugar for calls to built-in traits.
This means that comparison operators can be overridden for user-defined types.
The default meaning of the operators on standard types is given here.
`==`
: Equal to.
Calls the `eq` method on the `core::cmp::Eq` trait.
`!=`
: Unequal to.
Calls the `ne` method on the `core::cmp::Eq` trait.
`<`
: Less than.
Calls the `lt` method on the `core::cmp::Ord` trait.
`>`
: Greater than.
Calls the `gt` method on the `core::cmp::Ord` trait.
`<=`
: Less than or equal.
Calls the `le` method on the `core::cmp::Ord` trait.
`>=`
: Greater than or equal.
Calls the `ge` method on the `core::cmp::Ord` trait.
The binary comparison operators can be applied to any two operands of
the same type, and produce a boolean value.
#### Type cast expressions