used in float64 or float32 contexts

R=r
OCL=20297
CL=20297

- fixed printing of empty structs/interfaces
- enable two more tests

R=r
OCL=20296
CL=20296

- by default consider extra newlines in src for better formatting
- additional flags for control (-newlines, -maxnewlines, -optsemicolons)
- don't print ()'s around single anonymous result types

Status: Comparing the output of pretty with the input for larger files
shows mostly whitespace/formatting differences, which is what is desired.

TODO:
- Handling of overlong lines
- some esoteric cases which look funny

R=r
OCL=20293
CL=20293

R=ken
OCL=20289
CL=20289

default.  Fix PRETTY_OBJS to include compilation.o rather than
compilation.go.

R=gri
DELTA=10  (0 added, 8 deleted, 2 changed)
OCL=20248
CL=20257

R=ken
OCL=20188
CL=20188

R=rsc
DELTA=9  (9 added, 0 deleted, 0 changed)
OCL=20187
CL=20187

R=r
OCL=20185
CL=20185

- changed tab width to 8 chars by default to make test run properly
- excluded 4 files that are not idempotently printed
- fixed a couple of incorrect file position recordings in parser
- fine-tuned layout engine
- white-space formatting reasonable, but not perfect
- no handling of overlong lines
R=r

To use with smaller tabs:           pretty -tabwidth=4 file.go
To use with blanks instead of tabs: pretty -usetabs=0 file.go

OCL=20184
CL=20184

R=ken
OCL=20173
CL=20173

- comment printing still disabled by default because idempotency test fails
- whitespace control better but not perfect yet
- snapshot before making some heuristics changes

R=r
OCL=20151
CL=20151

TBR=r
OCL=20127
CL=20127

  for end of declarations, blocks, parameter lists, etc.
- use extra src positions to more accurately print comments
- fine-tuned low-level printing routine for comments
- added better debugging support

Status:
- comments now appear at the right place (inbetween the right tokens)
- newline control needs improvement (not very hard)
- comment printing disabled for now because pretty is not idempotent
with it; to enable: -comments

R=r
OCL=20079
CL=20079

way to integrate comments into the generated output
- various simplificatins and cleanups throughout

R=r
OCL=20062
CL=20062

sys·gosched+0x25 /home/rsc/go/src/runtime/proc.c:477
	sys·gosched()
chanrecv+0x29e /home/rsc/go/src/runtime/chan.c:277
	chanrecv(0x4be80, 0x0, 0x4cf88, 0x0, 0x0, ...)
sys·chanrecv1+0x5b /home/rsc/go/src/runtime/chan.c:355
	sys·chanrecv1(0x4be80, 0x0)
once·Server+0x26 /home/rsc/go/src/lib/strconv/atoi.go:-41
	once·Server()

the last line is broken (atoi.go:-41) but that's not new.

R=r
DELTA=46  (19 added, 14 deleted, 13 changed)
OCL=20018
CL=20026

not number of threads.  can still starve all the other threads,
but only by looping, not by waiting in a system call.

fix darwin syscall.Syscall6 bug.

fix chanclient bug.

delete $GOMAXPROCS from network tests.

add stripped down printf, sys.printhex to runtime.

R=r
DELTA=355  (217 added, 36 deleted, 102 changed)
OCL=20017
CL=20019

- added extra tests

R=r
DELTA=164  (107 added, 20 deleted, 37 changed)
OCL=20002
CL=20004

	warn about files with no tests
be clear about where testing warnings come from

R=r
DELTA=18  (12 added, 3 deleted, 3 changed)
OCL=19988
CL=19993

- runs all.bash

R=r
DELTA=121  (0 added, 121 deleted, 0 changed)
OCL=19960
CL=19983

fix up protocol buffers to use it.

R=rsc
DELTA=1232  (612 added, 572 deleted, 48 changed)
OCL=19964
CL=19981

r45=; 6.out
oops
panic PC=0x400316
0x400316?zi /home/rsc/go/src/runtime/rt0_amd64_linux.s:83
	main·g(4195177, 0, 4205661, ...)
	main·g(0x400369, 0x402c5d, 0x403e49, ...)
0x40034c?zi /home/rsc/go/src/runtime/x.go:24
	main·f(4205661, 0, 4210249, ...)
	main·f(0x402c5d, 0x403e49, 0x1, ...)
0x400368?zi /home/rsc/go/src/runtime/x.go:37
	main·main(4210249, 0, 1, ...)
	main·main(0x403e49, 0x1, 0x7fff9d894bd8, ...)
0x402c5c?zi /home/rsc/go/src/runtime/rt0_amd64.s:70
	mainstart(1, 0, 2643020760, ...)
	mainstart(0x1, 0x7fff9d894bd8, 0x0, ...)
r45=;

R=r
DELTA=251  (198 added, 25 deleted, 28 changed)
OCL=19965
CL=19979

R=r
DELTA=7  (7 added, 0 deleted, 0 changed)
OCL=19967
CL=19978

R=r
DELTA=150  (147 added, 0 deleted, 3 changed)
OCL=19968
CL=19977

- use more of the existing library code

R=r
OCL=19957
CL=19959

R=r
OCL=19953
CL=19953

R=ken
OCL=19943
CL=19943

R=r
DELTA=3  (3 added, 0 deleted, 0 changed)
OCL=19935
CL=19937

refine gotest's test selection criteria.

R=r
DELTA=1590  (745 added, 844 deleted, 1 changed)
OCL=19903
CL=19936

TBR=r
OCL=19924
CL=19934

so that compilation of other .6
will use the copy in goroot/pkg

R=r
DELTA=3  (1 added, 0 deleted, 2 changed)
OCL=19931
CL=19933

R=rsc
OCL=19929
CL=19929

R=rsc
OCL=19928
CL=19928

2. array bounds bug
3. ... optimization bug

R=r
OCL=19927
CL=19927

R=rsc
OCL=19926
CL=19926

*** Reason for rollback ***

broke build

*** Original change description ***

bufio.ReadRune

TBR=r
OCL=19923
CL=19923

*** Reason for rollback ***

broke build

*** Original change description ***

utf8: add InString routines for decoding in strings
reflect: add InterfaceValue.Get(), remove Empty
strconv: add Quote, CanBackquote
fmt:
	* %q go-quoted " string
	* %#q go-quoted ` string if possible, " string otherwise
	* %x hexadecimal string
	* anywhere a string is okay, *[]byte is okay
	* flags # 0 - + space
	* print value inside interface, not interface itself
	* tests

TBR=r
OCL=19920
CL=19920

reflect: add InterfaceValue.Get(), remove Empty
strconv: add Quote, CanBackquote
fmt:
	* %q go-quoted " string
	* %#q go-quoted ` string if possible, " string otherwise
	* %x hexadecimal string
	* anywhere a string is okay, *[]byte is okay
	* flags # 0 - + space
	* print value inside interface, not interface itself
	* tests

R=r
DELTA=756  (597 added, 121 deleted, 38 changed)
OCL=19888
CL=19916

R=rsc
DELTA=32  (29 added, 0 deleted, 3 changed)
OCL=19809
CL=19913

R=gri
DELTA=967  (468 added, 499 deleted, 0 changed)
OCL=19906
CL=19912

all could probably be made faster.

R=r
DELTA=929  (929 added, 0 deleted, 0 changed)
OCL=19879
CL=19911