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// Copyright © 2020 rsiddharth <s@ricketyspace.net>
// SPDX-License-Identifier: ISC
package lib
// Key: ASCII character; Value: score
var AsciiScores map[byte]int = make(map[byte]int, 0)
// Printable ASCII characters orrdered by frequency.
// (https://mdickens.me/typing/letter_frequency.html)
var PrintableAscii []byte = []byte{
' ', 'e', 't', 'a', 'o', 'i', 'n', 's', 'r', 'h', 'l', 'd',
'c', 'u', 'm', 'f', 'g', 'p', 'y', 'w', 'b', ',', '.',
'v', 'k', '-', '"', '_', '\'', 'x', ')', '(', ';', '0', 'j',
'1', 'q', '=', '2', ':', 'z', '/', '*', '!', '?', '$', '3',
'5', '>', '{', '}', '4', '9', '[', ']', '8', '6', '7', '\\',
'+', '|', '&', '<', '%', '@', '#', '^', '`', '~',
}
func init() {
// Initialize AsciiScores
for pos, a := range PrintableAscii {
AsciiScores[a] = 255 - pos
// Also add the uppercase version of ascii
// character if it exists.
au := ByteToUpper(a)
if a != au {
AsciiScores[au] = 255 - pos
}
}
}
func FillStr(a string, l int) string {
b := ""
if l < 1 {
return b
}
for i := 0; i < l; i++ {
b += a
}
return b
}
func FillBytes(c byte, l int) []byte {
if l < 1 {
return make([]byte, 0)
}
bs := make([]byte, l)
for i := 0; i < l; i++ {
bs[i] = c
}
return bs
}
func StrToBytes(s string) []byte {
bs := make([]byte, len(s))
for i := 0; i < len(s); i++ {
bs[i] = byte(s[i])
}
return bs
}
func BytesToStr(bs []byte) string {
s := ""
for i := 0; i < len(bs); i++ {
s += string(bs[i])
}
return s
}
// Strip space and newline characters from string.
func StripSpaceChars(s string) string {
ss := ""
for i := 0; i < len(s); i++ {
if s[i] == ' ' {
continue
}
if s[i] == '\n' {
continue
}
if s[i] == 0 { // NUL character
continue
}
ss += string(s[i])
}
return ss
}
func AlphaPunchScore(bs []byte) int {
s := 0
for i := 0; i < len(bs); i++ {
if isAlphaPunch(bs[i]) {
s += 1
}
}
return s
}
// Returns true if byte 'c' is a non-numeric character in the English language.
func isAlphaPunch(c byte) bool {
switch {
case 'A' <= c && c <= 'Z':
return true
case 'a' <= c && c <= 'z':
return true
case c == ' ' || c == '.':
return true
case c == ',' || c == '\'':
return true
case c == '"':
return true
}
return false
}
func NumToChar(n int64) byte {
if 0 <= n && n <= 9 {
return byte(48 + n)
}
return 0
}
func NumToStr(n int64) string {
s := ""
for n != 0 {
s = string(NumToChar(n%10)) + s
n /= 10
}
return s
}
func StrSplitAt(c byte, s string) []string {
l := make([]string, 0)
acc := ""
for i := 0; i < len(s); i++ {
if s[i] == c {
l = append(l, acc)
acc = ""
} else {
acc += string(s[i])
}
}
if len(acc) > 0 {
l = append(l, acc)
}
return l
}
func StrToUpper(s string) string {
us := ""
for i := 0; i < len(s); i++ {
us += string(ByteToUpper(s[i]))
}
return us
}
func ByteToUpper(b byte) byte {
if 'a' <= b && b <= 'z' {
return 'A' + (b - 'a')
} else {
return b
}
}
// Returns true if string 's' has string 'n' in it.
func StrHas(s, n string) bool {
for i := 0; i < len(s); i++ {
if s[i:i+len(n)] == n {
return true
}
}
return false
}
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