diff options
Diffstat (limited to 'libgo/go/math/big/ratconv.go')
| -rw-r--r-- | libgo/go/math/big/ratconv.go | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/libgo/go/math/big/ratconv.go b/libgo/go/math/big/ratconv.go index ef2b6750d0c..a6a401c8576 100644 --- a/libgo/go/math/big/ratconv.go +++ b/libgo/go/math/big/ratconv.go @@ -18,6 +18,9 @@ func ratTok(ch rune) bool { return strings.ContainsRune("+-/0123456789.eE", ch) } +var ratZero Rat +var _ fmt.Scanner = &ratZero // *Rat must implement fmt.Scanner + // Scan is a support routine for fmt.Scanner. It accepts the formats // 'e', 'E', 'f', 'F', 'g', 'G', and 'v'. All formats are equivalent. func (z *Rat) Scan(s fmt.ScanState, ch rune) error { @@ -36,8 +39,9 @@ func (z *Rat) Scan(s fmt.ScanState, ch rune) error { // SetString sets z to the value of s and returns z and a boolean indicating // success. s can be given as a fraction "a/b" or as a floating-point number -// optionally followed by an exponent. If the operation failed, the value of -// z is undefined but the returned value is nil. +// optionally followed by an exponent. The entire string (not just a prefix) +// must be valid for success. If the operation failed, the value of z is un- +// defined but the returned value is nil. func (z *Rat) SetString(s string) (*Rat, bool) { if len(s) == 0 { return nil, false @@ -49,9 +53,13 @@ func (z *Rat) SetString(s string) (*Rat, bool) { if _, ok := z.a.SetString(s[:sep], 0); !ok { return nil, false } - s = s[sep+1:] + r := strings.NewReader(s[sep+1:]) var err error - if z.b.abs, _, _, err = z.b.abs.scan(strings.NewReader(s), 0, false); err != nil { + if z.b.abs, _, _, err = z.b.abs.scan(r, 0, false); err != nil { + return nil, false + } + // entire string must have been consumed + if _, err = r.ReadByte(); err != io.EOF { return nil, false } if len(z.b.abs) == 0 { |