fmt.Print*: reimplement to switch on type first.

This shortens, simplifies and regularizes the code significantly.
(Improvements to reflect could make another step.)
Passes all.bash.

One semantic change occurs: The String() method changes
behavior. It used to run only for string formats such as %s and %q.
Instead, it now runs whenever the item has the method and the
result is then processed by the format as a string. Besides the
regularization, this has three effects:

	1) width is honored for String() items
	2) %x works for String() items
	3) implementations of String that merely recur will recur forever

Regarding point 3, example from the updated documentation:
	type X int
	func (x X) String() string { return Sprintf("%d", x) }
should cast the value before recurring:
	func (x X) String() string { return Sprintf("%d", int(x)) }

R=rsc
CC=golang-dev
http://codereview.appspot.com/1613045

1 files changed, 1 insertions, 24 deletions

diff --git a/src/pkg/fmt/scan_test.go b/src/pkg/fmt/scan_test.go
index 0ed53e886..d876adc9f 100644
--- a/src/pkg/fmt/scan_test.go
+++ b/src/pkg/fmt/scan_test.go
@@ -34,29 +34,6 @@ type ScanfMultiTest struct {
 	err    string
 }
 
-type (
-	renamedBool       bool
-	renamedInt        int
-	renamedInt8       int8
-	renamedInt16      int16
-	renamedInt32      int32
-	renamedInt64      int64
-	renamedUint       uint
-	renamedUint8      uint8
-	renamedUint16     uint16
-	renamedUint32     uint32
-	renamedUint64     uint64
-	renamedUintptr    uintptr
-	renamedString     string
-	renamedBytes      []byte
-	renamedFloat      float
-	renamedFloat32    float32
-	renamedFloat64    float64
-	renamedComplex    complex
-	renamedComplex64  complex64
-	renamedComplex128 complex128
-)
-
 var (
 	boolVal              bool
 	intVal               int
@@ -122,7 +99,7 @@ func (x *Xs) Scan(state ScanState, verb int) os.Error {
 	if err != nil {
 		return err
 	}
-	if !testing.MustCompile(string(verb) + "+").MatchString(tok) {
+	if !testing.MustCompile("^" + string(verb) + "+$").MatchString(tok) {
 		return os.ErrorString("syntax error for xs")
 	}
 	*x = Xs(tok)