RuneFunc implemented

This commit is contained in:
milarin 2023-01-20 23:59:36 +01:00
parent 3ca76e7670
commit 11b94aba9e
4 changed files with 102 additions and 17 deletions

View File

@ -119,16 +119,16 @@ func (r *Reader) UnreadRunes(n int) error {
return nil
}
// StringWhile reads runes and calls f for each one.
// It returns all runes as a string for which f returned true.
// It stops when f returns false or an error occured.
// The rune for which f returned false will not be unread.
func (r *Reader) StringWhile(f func(rn rune) bool) (string, error) {
// StringWhile reads runes and calls all functions for each one.
// It returns all runes as a string for which any function returned true.
// It stops when all functions returned false or an error occured.
// The rune for which that function returned false will not be unread.
func (r *Reader) StringWhile(f ...RuneFunc) (string, error) {
s := new(strings.Builder)
var rn rune
var err error
for rn, err = r.Rune(); err == nil && f(rn); rn, err = r.Rune() {
for rn, err = r.Rune(); err == nil && findFirstTrue(rn, f); rn, err = r.Rune() {
s.WriteRune(rn)
}
@ -136,8 +136,8 @@ func (r *Reader) StringWhile(f func(rn rune) bool) (string, error) {
}
// PeekStringWhile acts as StringWhile but does not advance reader position
func (r *Reader) PeekStringWhile(f func(rn rune) bool) (string, error) {
str, err := r.StringWhile(f)
func (r *Reader) PeekStringWhile(f ...RuneFunc) (string, error) {
str, err := r.StringWhile(f...)
if err != nil {
return "", err
}
@ -149,14 +149,23 @@ func (r *Reader) PeekStringWhile(f func(rn rune) bool) (string, error) {
return str, nil
}
// StringUntil is a shorthand for r.StringWhile(func(rn rune) bool { return !f(rn) })
func (r *Reader) StringUntil(f func(rn rune) bool) (string, error) {
return r.StringWhile(func(rn rune) bool { return !f(rn) })
// SkipStringWhile acts as StringWhile but discards the string
func (r *Reader) SkipStringWhile(f ...RuneFunc) error {
_, err := r.StringWhile(f...)
return err
}
// StringUntil reads runes and calls all functions for each one.
// It returns all runes as a string for which all functions returned true.
// It stops when any function returns false or an error occured.
// The rune for which that function returned false will not be unread.
func (r *Reader) StringUntil(f ...RuneFunc) (string, error) {
return r.StringWhile(func(rn rune) bool { return !findFirstTrue(rn, f) })
}
// PeekStringUntil acts as StringUntil but does not advance reader position
func (r *Reader) PeekStringUntil(f func(rn rune) bool) (string, error) {
str, err := r.StringUntil(f)
func (r *Reader) PeekStringUntil(f ...RuneFunc) (string, error) {
str, err := r.StringUntil(f...)
if err != nil {
return "", err
}
@ -168,6 +177,12 @@ func (r *Reader) PeekStringUntil(f func(rn rune) bool) (string, error) {
return str, nil
}
// SkipStringUntil acts as StringUntil but discards the string
func (r *Reader) SkipStringUntil(f ...RuneFunc) error {
_, err := r.StringUntil(f...)
return err
}
// Commit clears the internal buffer and therefore removes all data which were already read.
// After calling Commit any unreads will return ErrNothingToUnread until another read occured.
func (r *Reader) Commit() {

View File

@ -26,11 +26,11 @@ func TestPos(t *testing.T) {
func TestEOF(t *testing.T) {
r := NewReader(strings.NewReader("hello world\nasddsa"))
for line, err := r.StringUntil(isNewline); err == nil; line, err = r.StringUntil(isNewline) {
var line string
var err error
for line, err = r.StringUntil(IsNewLine); err == nil; line, err = r.StringUntil(IsNewLine) {
fmt.Println(line, err)
}
}
func isNewline(rn rune) bool {
return rn == '\n'
fmt.Println(line, err)
}

52
runefunc.go Normal file
View File

@ -0,0 +1,52 @@
package bufr
import "git.milar.in/milarin/ds"
type RuneFunc = func(rn rune) bool
func IsNewLine(rn rune) bool {
return rn == '\n'
}
func IsSpace(rn rune) bool {
return rn == ' '
}
func IsWhitespace(rn rune) bool {
return IsSpace(rn) || IsNewLine(rn)
}
func And(f ...RuneFunc) RuneFunc {
return func(rn rune) bool {
return findFirstFalse(rn, f)
}
}
func Or(f ...RuneFunc) RuneFunc {
return func(rn rune) bool {
return findFirstTrue(rn, f)
}
}
func Not(f RuneFunc) RuneFunc {
return func(rn rune) bool {
return !f(rn)
}
}
func Is(rn rune) RuneFunc {
return func(r rune) bool {
return rn == r
}
}
func OneOf(runes string) RuneFunc {
m := ds.NewSet[rune]()
for _, rn := range runes {
m.Add(rn)
}
return func(r rune) bool {
return m.Has(r)
}
}

View File

@ -13,3 +13,21 @@ func prependString(str string, r io.Reader) *bufio.Reader {
func prependRune(rn rune, r io.Reader) *bufio.Reader {
return prependString(string(rn), r)
}
func findFirstTrue(rn rune, functions []RuneFunc) bool {
for _, f := range functions {
if f(rn) {
return true
}
}
return false
}
func findFirstFalse(rn rune, functions []RuneFunc) bool {
for _, f := range functions {
if !f(rn) {
return false
}
}
return true
}