Reject '2' as a binary digit in internals of 'b' formatting

daboross · web-flow · commit 2c98378ace8d · 2017-11-28T21:35:18.000-08:00
I don't believe the previous code `0 ... 2` would run into any real problems, but it seems confusing to read, given that '2' is never a valid binary digit.

As far as I can tell this code is only ever called from within another private method in the trait which has logic to never hand it '2' anyways. I thought we could change this for clarity anyways.
diff --git a/src/libcore/fmt/num.rs b/src/libcore/fmt/num.rs
@@ -134,7 +134,7 @@ macro_rules! radix {
     }
 }
 
-radix! { Binary,    2, "0b", x @  0 ...  2 => b'0' + x }
+radix! { Binary,    2, "0b", x @  0 ...  1 => b'0' + x }
 radix! { Octal,     8, "0o", x @  0 ...  7 => b'0' + x }
 radix! { Decimal,  10, "",   x @  0 ...  9 => b'0' + x }
 radix! { LowerHex, 16, "0x", x @  0 ...  9 => b'0' + x,

Original file line number	Diff line number	Diff line change
`@@ -134,7 +134,7 @@ macro_rules! radix {`
`134`	`134`	`}`
`135`	`135`	`}`
`136`	`136`
`137`		`-radix! { Binary, 2, "0b", x @ 0 ... 2 => b'0' + x }`
	`137`	`+radix! { Binary, 2, "0b", x @ 0 ... 1 => b'0' + x }`
`138`	`138`	`radix! { Octal, 8, "0o", x @ 0 ... 7 => b'0' + x }`
`139`	`139`	`radix! { Decimal, 10, "", x @ 0 ... 9 => b'0' + x }`
`140`	`140`	`radix! { LowerHex, 16, "0x", x @ 0 ... 9 => b'0' + x,`