diff options
Diffstat (limited to 'libgo/go/math/rand/rand.go')
| -rw-r--r-- | libgo/go/math/rand/rand.go | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/libgo/go/math/rand/rand.go b/libgo/go/math/rand/rand.go index 8955219..94f84a8 100644 --- a/libgo/go/math/rand/rand.go +++ b/libgo/go/math/rand/rand.go @@ -49,9 +49,10 @@ func (r *Rand) Int() int { } // Int63n returns, as an int64, a non-negative pseudo-random number in [0,n). +// It panics if n <= 0. func (r *Rand) Int63n(n int64) int64 { if n <= 0 { - return 0 + panic("invalid argument to Int63n") } max := int64((1 << 63) - 1 - (1<<63)%uint64(n)) v := r.Int63() @@ -62,9 +63,10 @@ func (r *Rand) Int63n(n int64) int64 { } // Int31n returns, as an int32, a non-negative pseudo-random number in [0,n). +// It panics if n <= 0. func (r *Rand) Int31n(n int32) int32 { if n <= 0 { - return 0 + panic("invalid argument to Int31n") } max := int32((1 << 31) - 1 - (1<<31)%uint32(n)) v := r.Int31() @@ -75,7 +77,11 @@ func (r *Rand) Int31n(n int32) int32 { } // Intn returns, as an int, a non-negative pseudo-random number in [0,n). +// It panics if n <= 0. func (r *Rand) Intn(n int) int { + if n <= 0 { + panic("invalid argument to Intn") + } if n <= 1<<31-1 { return int(r.Int31n(int32(n))) } @@ -125,12 +131,15 @@ func Int31() int32 { return globalRand.Int31() } func Int() int { return globalRand.Int() } // Int63n returns, as an int64, a non-negative pseudo-random number in [0,n). +// It panics if n <= 0. func Int63n(n int64) int64 { return globalRand.Int63n(n) } // Int31n returns, as an int32, a non-negative pseudo-random number in [0,n). +// It panics if n <= 0. func Int31n(n int32) int32 { return globalRand.Int31n(n) } // Intn returns, as an int, a non-negative pseudo-random number in [0,n). +// It panics if n <= 0. func Intn(n int) int { return globalRand.Intn(n) } // Float64 returns, as a float64, a pseudo-random number in [0.0,1.0). |