Also fix a bug: precision was in terms of bytes; should be runes.
Fixes#1652.
R=rsc, bradfitzgo, r2, bradfitzwork
CC=golang-dev
https://golang.org/cl/4280086
When writing custom scanners, I found that
Token itself was rarely useful, as I did not always
want to stop at white space. This change makes
it possible to stop at any class of characters
while reusing the buffer within State.
(also fix a bug in Token)
R=r, r2
CC=golang-dev
https://golang.org/cl/4243055
Detect when scan is being called recursively and
re-use the same scan state.
On my machine, for a recursion-heavy benchmark, this
results in 44x speed up. This does impose a 4% penalty
on the non-recursive case, which can be removed by
heap-allocating the saved state, at 40% performance penalty
on the recursive case. Either way is fine with me.
R=r
CC=golang-dev
https://golang.org/cl/4253049
Add a new Read method to ScanState so that it
satisfies the io.Reader interface; rename
Getrune and Ungetrune to ReadRune and UnreadRune.
Make sure ReadRune does not read past width restrictions;
remove now-unnecessary Width method from ScanState.
Also make the documentation a little clearer as to
how ReadRune and UnreadRune are used.
R=r, r2
CC=golang-dev
https://golang.org/cl/4240056
signed or unsigned integers using %v or the formatless scanner.
That is, Sscan("0x11", &i) or Sscanf("0x11", "%v", &i) will now
set i to 17. If a format other than %v is presented, the behavior
is as before.
Fixes#1469.
R=rsc
CC=golang-dev
https://golang.org/cl/4131042
The old loop was a bit odd; change it to be more regular.
This also enables a diagnostic for Printf("%", 3): %!(NOVERB)
R=rsc, Kyle C
CC=golang-dev
https://golang.org/cl/3749044
I have written a tool to verify Printf calls, and although it's not
ready to be reviewed yet it's already uncovered a spate of problems
in the repository. I'm sending this CL to break the changes into
pieces; as the tool improves it will find more, I'm sure.
R=rsc
CC=golang-dev
https://golang.org/cl/3427043
fmt.Printf("%U", 1) yields "U+0001"
It's essentially "U+%.4x" but lets you override the precision works in scan, too.
R=rsc
CC=golang-dev
https://golang.org/cl/3423043
Rather than updating the stripped-down regexp implementation embedded
in testing, delete it by passing the one function we need from the package
main file created by gotest.
R=rsc
CC=golang-dev
https://golang.org/cl/2761043
This crops up in a lot of places.
It's just a one-liner, but doesn't add any dependancies.
Seems worth it.
R=r, r2
CC=golang-dev
https://golang.org/cl/2344041
the solution must work around a weakness in the reflection library:
there is no way to do type-safe conversions under reflection.
R=rsc
CC=golang-dev
https://golang.org/cl/2000041