Function Number

common.go:211–512

Number minifies a given byte slice containing a number and removes superfluous characters.

(num []byte, prec int)

// Number minifies a given byte slice containing a number and removes superfluous characters.
func Number(num []byte, prec int) []byte {
	if len(num) <= 1 {
		return num
	}

	// omit first + and register mantissa start and end, whether it's negative and the exponent
	neg := false
	start := 0
	dot := -1
	end := len(num)
	origExp := 0
	if num[0] == '+' || num[0] == '-' {
		if num[0] == '-' {
			neg = true
		}
		start++
	}
	for i, c := range num[start:] {
		if c == '.' {
			dot = start + i
		} else if c == 'e' || c == 'E' {
			end = start + i
			i += start + 1
			if i < len(num) && num[i] == '+' {
				i++
			}
			if tmpOrigExp, n := strconv.ParseInt(num[i:]); 0 < n && int64(MinInt) <= tmpOrigExp && tmpOrigExp <= int64(MaxInt) {
				// range checks for when int is 32 bit
				origExp = int(tmpOrigExp)
			} else {
				return num
			}
			break
		}
	}
	if dot == -1 {
		dot = end
	}

	// trim leading zeros but leave at least one digit
	for start < end-1 && num[start] == '0' {
		start++
	}
	// trim trailing zeros
	i := end - 1
	for ; dot < i; i-- {
		if num[i] != '0' {
			end = i + 1
			break
		}
	}
	if i == dot {
		end = dot
		if start == end {
			num[start] = '0'
			return num[start : start+1]
		}
	} else if start == end-1 && num[start] == '0' {