rust/src/libcore/to_str.rs
Tim Chevalier 5a8ba073bc Make to_str pure and fix const parameters for str-mutating functions
Two separate changes that got intertwined (sorry):

Make to_str pure. Closes #3691

In str, change functions like push_char to take an &mut str instead of
an &str. Closes #3710
2012-10-11 14:17:59 -07:00

143 lines
3.5 KiB
Rust

/*!
The `ToStr` trait for converting to strings
*/
// NB: transitionary, de-mode-ing.
#[forbid(deprecated_mode)];
#[forbid(deprecated_pattern)];
pub trait ToStr { pure fn to_str() -> ~str; }
impl int: ToStr {
pure fn to_str() -> ~str { int::str(self) }
}
impl i8: ToStr {
pure fn to_str() -> ~str { i8::str(self) }
}
impl i16: ToStr {
pure fn to_str() -> ~str { i16::str(self) }
}
impl i32: ToStr {
pure fn to_str() -> ~str { i32::str(self) }
}
impl i64: ToStr {
pure fn to_str() -> ~str { i64::str(self) }
}
impl uint: ToStr {
pure fn to_str() -> ~str { uint::str(self) }
}
impl u8: ToStr {
pure fn to_str() -> ~str { u8::str(self) }
}
impl u16: ToStr {
pure fn to_str() -> ~str { u16::str(self) }
}
impl u32: ToStr {
pure fn to_str() -> ~str { u32::str(self) }
}
impl u64: ToStr {
pure fn to_str() -> ~str { u64::str(self) }
}
impl float: ToStr {
pure fn to_str() -> ~str { float::to_str(self, 4u) }
}
impl f32: ToStr {
pure fn to_str() -> ~str { float::to_str(self as float, 4u) }
}
impl f64: ToStr {
pure fn to_str() -> ~str { float::to_str(self as float, 4u) }
}
impl bool: ToStr {
pure fn to_str() -> ~str { bool::to_str(self) }
}
impl (): ToStr {
pure fn to_str() -> ~str { ~"()" }
}
impl ~str: ToStr {
pure fn to_str() -> ~str { copy self }
}
impl &str: ToStr {
pure fn to_str() -> ~str { str::from_slice(self) }
}
impl @str: ToStr {
pure fn to_str() -> ~str { str::from_slice(self) }
}
impl<A: ToStr Copy, B: ToStr Copy> (A, B): ToStr {
pure fn to_str() -> ~str {
let (a, b) = self;
~"(" + a.to_str() + ~", " + b.to_str() + ~")"
}
}
impl<A: ToStr Copy, B: ToStr Copy, C: ToStr Copy> (A, B, C): ToStr {
pure fn to_str() -> ~str {
let (a, b, c) = self;
~"(" + a.to_str() + ~", " + b.to_str() + ~", " + c.to_str() + ~")"
}
}
impl<A: ToStr> ~[A]: ToStr {
pure fn to_str() -> ~str unsafe {
// Bleh -- not really unsafe
// push_str and push_char
let mut acc = ~"[", first = true;
for vec::each(self) |elt| unsafe {
if first { first = false; }
else { str::push_str(&mut acc, ~", "); }
str::push_str(&mut acc, elt.to_str());
}
str::push_char(&mut acc, ']');
move acc
}
}
impl<A: ToStr> @A: ToStr {
pure fn to_str() -> ~str { ~"@" + (*self).to_str() }
}
impl<A: ToStr> ~A: ToStr {
pure fn to_str() -> ~str { ~"~" + (*self).to_str() }
}
#[cfg(test)]
#[allow(non_implicitly_copyable_typarams)]
mod tests {
#[test]
fn test_simple_types() {
assert 1.to_str() == ~"1";
assert (-1).to_str() == ~"-1";
assert 200u.to_str() == ~"200";
assert 2u8.to_str() == ~"2";
assert true.to_str() == ~"true";
assert false.to_str() == ~"false";
assert ().to_str() == ~"()";
assert (~"hi").to_str() == ~"hi";
assert (@"hi").to_str() == ~"hi";
}
#[test]
fn test_tuple_types() {
assert (1, 2).to_str() == ~"(1, 2)";
assert (~"a", ~"b", false).to_str() == ~"(a, b, false)";
assert ((), ((), 100)).to_str() == ~"((), ((), 100))";
}
#[test]
#[ignore]
fn test_vectors() {
let x: ~[int] = ~[];
assert x.to_str() == ~"~[]";
assert (~[1]).to_str() == ~"~[1]";
assert (~[1, 2, 3]).to_str() == ~"~[1, 2, 3]";
assert (~[~[], ~[1], ~[1, 1]]).to_str() ==
~"~[~[], ~[1], ~[1, 1]]";
}
#[test]
fn test_pointer_types() {
assert (@1).to_str() == ~"@1";
assert (~(true, false)).to_str() == ~"~(true, false)";
}
}