Interesting that Fprintf can do zero mallocs.
(Sprintf must allocate the returned string.)
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/4977049
The C-stdlib heritage of printf/fprintf/sprintf has two odd
aspects for precisions of zero with integers. First, the zero
can be specified in any of these ways, "%4.0d", "%.0d" and
"%.d" which was not previously supported here. Secondly, the
seemingly universal interpretation of precision for integers
is that precision==0 and value==0 means print nothing at all.
The code here now handles this for integers just as the code
in big/int.c does the same for the Int type. New tests are
added to fmt_test.go to verify these changes.
R=r, r
CC=golang-dev
https://golang.org/cl/4717045
The public godoc looked confused. I imagine these were
written before current conventions were established.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4662060
Users of the Scan() infrastructure that employ ReadRune() rather than
Token() need a way to skip leading spaces and newlines as set by the
the parent, Fscan(), Fscanln, or Fscanf(). As the internal methods and
boolean flags are not exported, this new function was added here and
in the Int and Nat Scan() functions of the big package. (fmt.Rat did
not need change since it uses Token()) Also added Printf style format
code support to int types and tests for same to int_test.go
R=r, r, gri, mtj
CC=golang-dev
https://golang.org/cl/4634074
This is a core API change.
1) gofix misc src
2) Manual adjustments to the following files under src/pkg:
gob/decode.go
rpc/client.go
os/error.go
io/io.go
bufio/bufio.go
http/request.go
websocket/client.go
as well as:
src/cmd/gofix/testdata/*.go.in (reverted)
test/fixedbugs/bug243.go
3) Implemented gofix patch (oserrorstring.go) and test case (oserrorstring_test.go)
Compiles and runs all tests.
R=r, rsc, gri
CC=golang-dev
https://golang.org/cl/4607052
This change causes Print et al. to catch panics generated by
calls to String, GoString, and Format. The panic is formatted
into the output stream as an error, but the program continues.
As a special case, if the argument was a nil pointer, the
result is just "<nil>", because that's almost certainly enough
information and handles the very common case of String
methods that don't guard against nil.
Scan does not want this change. Input must work; output can
be for debugging and it's nice to get output even when you
make a mistake.
R=dsymonds, r, adg, gri, rsc, gri
CC=golang-dev
https://golang.org/cl/4640043
%+q uses strconv.Quote[Rune]ToASCII, guaranteeing ASCII-only output.
%#U a quoted character if the rune is printable: 'x'=U+0078; otherwise
it's as before: U+000A.
R=golang-dev, gri, rsc
CC=golang-dev
https://golang.org/cl/4589047
add QuoteToASCII.
The Quote and QuoteRune functions now let printable
runes (as defined by unicode.IsPrint) through. When
true 7-bit clean stuff is necessary, there are now two
new functions: QuoteToASCII and QuoteRuneToASCII.
Printf("%q") uses Quote. To get the old behavior, it
will now be necessary to say
Printf("%s", strconv.QuoteToASCII(s))
but that should rarely be necessary.
R=golang-dev, gri, r
CC=golang-dev
https://golang.org/cl/4561061
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
Rob Pike
Michael T. Jones
Robert Griesemer
Brad Fitzpatrick
Russ Cox
Evan Shaw
Ian Lance Taylor
Roger Peppe
Robert Hencke
Kyle Consalus