fx/utils.go

package main

import (
	"regexp"
	"strings"
)

var identifier = regexp.MustCompile(`^[a-zA-Z_][a-zA-Z0-9_]*$`)

func isHexDigit(ch byte) bool {
	return (ch >= '0' && ch <= '9') || (ch >= 'a' && ch <= 'f') || (ch >= 'A' && ch <= 'F')
}

func isDigit(ch byte) bool {
	return ch >= '0' && ch <= '9'
}

func max(i, j int) int {
	if i > j {
		return i
	}
	return j
}

func regexCase(code string) (string, bool) {
	if strings.HasSuffix(code, "/i") {
		return code[:len(code)-2], true
	} else if strings.HasSuffix(code, "/") {
		return code[:len(code)-1], false
	} else {
		return code, true
	}
}

func flex(width int, a, b string) string {
	return a + strings.Repeat(" ", max(1, width-len(a)-len(b))) + b
}

func safeSlice(b []byte, start, end int) []byte {
	length := len(b)
	if start > length {
		start = length
	}
	if end > length {
		end = length
	}
	if start < 0 {
		start = 0
	}
	if end < 0 {
		end = 0
	}
	if start > end {
		start = end
	}
	return b[start:end]
}