package markdownish

import (
    "strings"
    "unicode"
    "unicode/utf8"
)

// TODO to avoid having to include unicode's tables, self-implement unicode.IsSpace
func unicodeIsSpace(r rune) bool {
    return unicode.IsSpace(r)
}

// TODO Remove in Go 1.21.
func max(x, y int) int {
    if x >= y {
        return x
    }
    return y
}

func escape(raw string, allowed func(rune) bool) string {
    b := new(strings.Builder)
    for len(raw) > 0 {
        r, size := utf8.DecodeRuneInString(raw)
        raw = raw[size:]
        if !allowed(r) {
            r = utf8.RuneError
        }
        b.WriteRune(r)
    }
    return b.String()
}