diff options
Diffstat (limited to 'src/lib/strings.go')
-rw-r--r-- | src/lib/strings.go | 69 |
1 files changed, 67 insertions, 2 deletions
diff --git a/src/lib/strings.go b/src/lib/strings.go index 2f3b630df..98650b547 100644 --- a/src/lib/strings.go +++ b/src/lib/strings.go @@ -168,7 +168,7 @@ export func atoi(s string) (i int, ok bool) { return i, okok } -export func itol(i int64) string { +export func ltoa(i int64) string { if i == 0 { return "0" } @@ -197,5 +197,70 @@ export func itol(i int64) string { } export func itoa(i int) string { - return itol(int64(i)); + return ltoa(int64(i)); +} + +// Convert float64 to string. No control over format. +// Result not great; only useful for simple debugging. +export func dtoa(v float64) string { + var buf [20]byte; + + const n = 7; // digits printed + e := 0; // exp + var sign byte = '+'; + if(v != 0) { + // sign + if(v < 0) { + v = -v; + sign = '-'; + } + + // normalize + for v >= 10 { + e++; + v /= 10; + } + for v < 1 { + e--; + v *= 10; + } + + // round + var h float64 = 5; + for i := 0; i < n; i++ { + h /= 10; + } + v += h; + if v >= 10 { + e++; + v /= 10; + } + } + + // format +d.dddd+edd + buf[0] = sign; + for i := 0; i < n; i++ { + s := int64(v); + buf[i+2] = byte(s)+'0'; + v -= float64(s); + v *= 10; + } + buf[1] = buf[2]; + buf[2] = '.'; + + buf[n+2] = 'e'; + buf[n+3] = '+'; + if e < 0 { + e = -e; + buf[n+3] = '-'; + } + + // TODO: exponents > 99? + buf[n+4] = byte((e/10) + '0'); + buf[n+5] = byte((e%10) + '0'); + return string(buf)[0:n+6]; // TODO: should be able to slice buf +} + +export func ftoa(v float) string { + return dtoa(float64(v)); } |