diff options
Diffstat (limited to 'src/libcore/option.rs')
| -rw-r--r-- | src/libcore/option.rs | 119 |
1 files changed, 46 insertions, 73 deletions
diff --git a/src/libcore/option.rs b/src/libcore/option.rs index 6ab9a86d8f3..6bd326186cb 100644 --- a/src/libcore/option.rs +++ b/src/libcore/option.rs @@ -9,18 +9,18 @@ */ // NB: transitionary, de-mode-ing. -#[forbid(deprecated_mode)]; +#[warn(deprecated_mode)]; #[forbid(deprecated_pattern)]; use cmp::Eq; /// The option type -enum Option<T> { +pub enum Option<T> { None, Some(T), } -pure fn get<T: Copy>(opt: &Option<T>) -> T { +pub pure fn get<T: Copy>(opt: &Option<T>) -> T { /*! * Gets the value out of an option * @@ -30,12 +30,12 @@ pure fn get<T: Copy>(opt: &Option<T>) -> T { */ match *opt { - Some(x) => return x, + Some(copy x) => return x, None => fail ~"option::get none" } } -pure fn get_ref<T>(opt: &r/Option<T>) -> &r/T { +pub pure fn get_ref<T>(opt: &r/Option<T>) -> &r/T { /*! * Gets an immutable reference to the value inside an option. * @@ -49,7 +49,7 @@ pure fn get_ref<T>(opt: &r/Option<T>) -> &r/T { } } -pure fn expect<T: Copy>(opt: &Option<T>, +reason: ~str) -> T { +pub pure fn expect<T: Copy>(opt: &Option<T>, reason: ~str) -> T { /*! * Gets the value out of an option, printing a specified message on * failure @@ -58,22 +58,17 @@ pure fn expect<T: Copy>(opt: &Option<T>, +reason: ~str) -> T { * * Fails if the value equals `none` */ - match *opt { Some(x) => x, None => fail reason } + match *opt { Some(copy x) => x, None => fail reason } } -pure fn map<T, U>(opt: &Option<T>, f: fn(T) -> U) -> Option<U> { - //! Maps a `some` value from one type to another - - match *opt { Some(x) => Some(f(x)), None => None } -} - -pure fn map_ref<T, U>(opt: &Option<T>, f: fn(x: &T) -> U) -> Option<U> { +pub pure fn map<T, U>(opt: &Option<T>, f: fn(x: &T) -> U) -> Option<U> { //! Maps a `some` value by reference from one type to another match *opt { Some(ref x) => Some(f(x)), None => None } } -pure fn map_consume<T, U>(+opt: Option<T>, f: fn(+v: T) -> U) -> Option<U> { +pub pure fn map_consume<T, U>(opt: Option<T>, + f: fn(v: T) -> U) -> Option<U> { /*! * As `map`, but consumes the option and gives `f` ownership to avoid * copying. @@ -81,17 +76,23 @@ pure fn map_consume<T, U>(+opt: Option<T>, f: fn(+v: T) -> U) -> Option<U> { if opt.is_some() { Some(f(option::unwrap(move opt))) } else { None } } -pure fn chain<T, U>(opt: &Option<T>, f: fn(T) -> Option<U>) -> Option<U> { +pub pure fn chain<T, U>(opt: Option<T>, + f: fn(t: T) -> Option<U>) -> Option<U> { /*! * Update an optional value by optionally running its content through a * function that returns an option. */ - match *opt { Some(x) => f(x), None => None } + // XXX write with move match + if opt.is_some() { + f(unwrap(opt)) + } else { + None + } } -pure fn chain_ref<T, U>(opt: &Option<T>, - f: fn(x: &T) -> Option<U>) -> Option<U> { +pub pure fn chain_ref<T, U>(opt: &Option<T>, + f: fn(x: &T) -> Option<U>) -> Option<U> { /*! * Update an optional value by optionally running its content by reference * through a function that returns an option. @@ -100,7 +101,7 @@ pure fn chain_ref<T, U>(opt: &Option<T>, match *opt { Some(ref x) => f(x), None => None } } -pure fn or<T>(+opta: Option<T>, +optb: Option<T>) -> Option<T> { +pub pure fn or<T>(opta: Option<T>, optb: Option<T>) -> Option<T> { /*! * Returns the leftmost some() value, or none if both are none. */ @@ -111,7 +112,7 @@ pure fn or<T>(+opta: Option<T>, +optb: Option<T>) -> Option<T> { } #[inline(always)] -pure fn while_some<T>(+x: Option<T>, blk: fn(+v: T) -> Option<T>) { +pub pure fn while_some<T>(x: Option<T>, blk: fn(v: T) -> Option<T>) { //! Applies a function zero or more times until the result is none. let mut opt <- x; @@ -120,54 +121,38 @@ pure fn while_some<T>(+x: Option<T>, blk: fn(+v: T) -> Option<T>) { } } -pure fn is_none<T>(opt: &Option<T>) -> bool { +pub pure fn is_none<T>(opt: &Option<T>) -> bool { //! Returns true if the option equals `none` match *opt { None => true, Some(_) => false } } -pure fn is_some<T>(opt: &Option<T>) -> bool { +pub pure fn is_some<T>(opt: &Option<T>) -> bool { //! Returns true if the option contains some value !is_none(opt) } -pure fn get_default<T: Copy>(opt: &Option<T>, +def: T) -> T { +pub pure fn get_default<T: Copy>(opt: &Option<T>, def: T) -> T { //! Returns the contained value or a default - match *opt { Some(x) => x, None => def } + match *opt { Some(copy x) => x, None => def } } -pure fn map_default<T, U>(opt: &Option<T>, +def: U, f: fn(T) -> U) -> U { - //! Applies a function to the contained value or returns a default - - match *opt { None => move def, Some(t) => f(t) } -} - -// This should replace map_default. -pure fn map_default_ref<T, U>(opt: &Option<T>, +def: U, +pub pure fn map_default<T, U>(opt: &Option<T>, def: U, f: fn(x: &T) -> U) -> U { //! Applies a function to the contained value or returns a default match *opt { None => move def, Some(ref t) => f(t) } } -// This should change to by-copy mode; use iter_ref below for by reference -pure fn iter<T>(opt: &Option<T>, f: fn(T)) { - //! Performs an operation on the contained value or does nothing - - match *opt { None => (), Some(t) => f(t) } -} - -pure fn iter_ref<T>(opt: &Option<T>, f: fn(x: &T)) { +pub pure fn iter<T>(opt: &Option<T>, f: fn(x: &T)) { //! Performs an operation on the contained value by reference match *opt { None => (), Some(ref t) => f(t) } } -// tjc: shouldn't this be - instead of +? -// then could get rid of some superfluous moves #[inline(always)] -pure fn unwrap<T>(+opt: Option<T>) -> T { +pub pure fn unwrap<T>(opt: Option<T>) -> T { /*! * Moves a value out of an option type and returns it. * @@ -182,12 +167,12 @@ pure fn unwrap<T>(+opt: Option<T>) -> T { /// The ubiquitous option dance. #[inline(always)] -fn swap_unwrap<T>(opt: &mut Option<T>) -> T { +pub fn swap_unwrap<T>(opt: &mut Option<T>) -> T { if opt.is_none() { fail ~"option::swap_unwrap none" } unwrap(util::replace(opt, None)) } -pure fn unwrap_expect<T>(+opt: Option<T>, reason: &str) -> T { +pub pure fn unwrap_expect<T>(opt: Option<T>, reason: &str) -> T { //! As unwrap, but with a specified failure message. if opt.is_none() { fail reason.to_unique(); } unwrap(move opt) @@ -195,22 +180,10 @@ pure fn unwrap_expect<T>(+opt: Option<T>, reason: &str) -> T { // Some of these should change to be &Option<T>, some should not. See below. impl<T> Option<T> { - /** - * Update an optional value by optionally running its content through a - * function that returns an option. - */ - pure fn chain<U>(f: fn(T) -> Option<U>) -> Option<U> { chain(&self, f) } - /// Applies a function to the contained value or returns a default - pure fn map_default<U>(+def: U, f: fn(T) -> U) -> U - { map_default(&self, move def, f) } - /// Performs an operation on the contained value or does nothing - pure fn iter(f: fn(T)) { iter(&self, f) } /// Returns true if the option equals `none` pure fn is_none() -> bool { is_none(&self) } /// Returns true if the option contains some value pure fn is_some() -> bool { is_some(&self) } - /// Maps a `some` value from one type to another - pure fn map<U>(f: fn(T) -> U) -> Option<U> { map(&self, f) } } impl<T> &Option<T> { @@ -222,12 +195,12 @@ impl<T> &Option<T> { chain_ref(self, f) } /// Applies a function to the contained value or returns a default - pure fn map_default_ref<U>(+def: U, f: fn(x: &T) -> U) -> U - { map_default_ref(self, move def, f) } + pure fn map_default<U>(def: U, f: fn(x: &T) -> U) -> U + { map_default(self, move def, f) } /// Performs an operation on the contained value by reference - pure fn iter_ref(f: fn(x: &T)) { iter_ref(self, f) } + pure fn iter(f: fn(x: &T)) { iter(self, f) } /// Maps a `some` value from one type to another by reference - pure fn map_ref<U>(f: fn(x: &T) -> U) -> Option<U> { map_ref(self, f) } + pure fn map<U>(f: fn(x: &T) -> U) -> Option<U> { map(self, f) } /// Gets an immutable reference to the value inside a `some`. pure fn get_ref() -> &self/T { get_ref(self) } } @@ -241,7 +214,7 @@ impl<T: Copy> Option<T> { * Fails if the value equals `none` */ pure fn get() -> T { get(&self) } - pure fn get_default(+def: T) -> T { get_default(&self, def) } + pure fn get_default(def: T) -> T { get_default(&self, def) } /** * Gets the value out of an option, printing a specified message on * failure @@ -250,9 +223,9 @@ impl<T: Copy> Option<T> { * * Fails if the value equals `none` */ - pure fn expect(+reason: ~str) -> T { expect(&self, reason) } + pure fn expect(reason: ~str) -> T { expect(&self, reason) } /// Applies a function zero or more times until the result is none. - pure fn while_some(blk: fn(+v: T) -> Option<T>) { while_some(self, blk) } + pure fn while_some(blk: fn(v: T) -> Option<T>) { while_some(self, blk) } } impl<T: Eq> Option<T> : Eq { @@ -264,11 +237,11 @@ impl<T: Eq> Option<T> : Eq { Some(_) => false } } - Some(self_contents) => { + Some(ref self_contents) => { match (*other) { None => false, Some(ref other_contents) => - self_contents.eq(other_contents) + (*self_contents).eq(other_contents) } } } @@ -279,20 +252,20 @@ impl<T: Eq> Option<T> : Eq { #[test] fn test_unwrap_ptr() { let x = ~0; - let addr_x = ptr::addr_of(*x); + let addr_x = ptr::p2::addr_of(&(*x)); let opt = Some(x); let y = unwrap(opt); - let addr_y = ptr::addr_of(*y); + let addr_y = ptr::p2::addr_of(&(*y)); assert addr_x == addr_y; } #[test] fn test_unwrap_str() { let x = ~"test"; - let addr_x = str::as_buf(x, |buf, _len| ptr::addr_of(buf)); - let opt = Some(x); - let y = unwrap(opt); - let addr_y = str::as_buf(y, |buf, _len| ptr::addr_of(buf)); + let addr_x = str::as_buf(x, |buf, _len| buf); + let opt = Some(move x); + let y = unwrap(move opt); + let addr_y = str::as_buf(y, |buf, _len| buf); assert addr_x == addr_y; } |