func Center(str string, length int, pad string) string
Center returns a string with pad string at both side if str's rune length is smaller than length. If str's rune length is larger than length, str itself will be returned.
If pad is an empty string, str will be returned.
Samples:
Center("hello", 4, " ") => "hello"
Center("hello", 10, " ") => " hello "
Center("hello", 10, "123") => "12hello123"
func Count(str, pattern string) int
Count how many runes in str match the pattern. Pattern is defined in Translate function.
Samples:
Count("hello", "aeiou") => 3
Count("hello", "a-k") => 3
Count("hello", "^a-k") => 2
func Delete(str, pattern string) string
Delete runes in str matching the pattern. Pattern is defined in Translate function.
Samples:
Delete("hello", "aeiou") => "hll"
Delete("hello", "a-k") => "llo"
Delete("hello", "^a-k") => "he"
func ExpandTabs(str string, tabSize int) string
ExpandTabs can expand tabs ('\t') rune in str to one or more spaces dpending on current column and tabSize. The column number is reset to zero after each newline ('\n') occurring in the str.
ExpandTabs uses RuneWidth to decide rune's width. For example, CJK characters will be treated as two characters.
If tabSize <= 0, ExpandTabs panics with error.
Samples:
ExpandTabs("a\tbc\tdef\tghij\tk", 4) => "a bc def ghij k"
ExpandTabs("abcdefg\thij\nk\tl", 4) => "abcdefg hij\nk l"
ExpandTabs("z中\t文\tw", 4) => "z中 文 w"
func FirstRuneToLower(str string) string
FirstRuneToLower converts first rune to lower case if necessary.
func FirstRuneToUpper(str string) string
FirstRuneToUpper converts first rune to upper case if necessary.
func Insert(dst, src string, index int) string
Insert src into dst at given rune index. Index is counted by runes instead of bytes.
If index is out of range of dst, panic with out of range.
func LastPartition(str, sep string) (head, match, tail string)
LastPartition splits a string by last instance of sep into three parts. The return value is a slice of strings with head, match and tail.
If str contains sep, for example "hello" and "l", LastPartition returns
"hel", "l", "o"
If str doesn't contain sep, for example "hello" and "x", LastPartition returns
"", "", "hello"
func LeftJustify(str string, length int, pad string) string
LeftJustify returns a string with pad string at right side if str's rune length is smaller than length. If str's rune length is larger than length, str itself will be returned.
If pad is an empty string, str will be returned.
Samples:
LeftJustify("hello", 4, " ") => "hello"
LeftJustify("hello", 10, " ") => "hello "
LeftJustify("hello", 10, "123") => "hello12312"
func Len(str string) int
Len returns str's utf8 rune length.
func Partition(str, sep string) (head, match, tail string)
Partition splits a string by sep into three parts. The return value is a slice of strings with head, match and tail.
If str contains sep, for example "hello" and "l", Partition returns
"he", "l", "lo"
If str doesn't contain sep, for example "hello" and "x", Partition returns
"hello", "", ""
func Reverse(str string) string
Reverse a utf8 encoded string.
func RightJustify(str string, length int, pad string) string
RightJustify returns a string with pad string at left side if str's rune length is smaller than length. If str's rune length is larger than length, str itself will be returned.
If pad is an empty string, str will be returned.
Samples:
RightJustify("hello", 4, " ") => "hello"
RightJustify("hello", 10, " ") => " hello"
RightJustify("hello", 10, "123") => "12312hello"
func RuneWidth(r rune) int
RuneWidth returns character width in monotype font. Multi-byte characters are usually twice the width of single byte characters.
Algorithm comes from `mb_strwidth` in PHP. http://php.net/manual/en/function.mb-strwidth.php
func Scrub(str, repl string) string
Scrub scrubs invalid utf8 bytes with repl string. Adjacent invalid bytes are replaced only once.
func Shuffle(str string) string
Shuffle randomizes runes in a string and returns the result. It uses default random source in `math/rand`.
func ShuffleSource(str string, src rand.Source) string
ShuffleSource randomizes runes in a string with given random source.
func Slice(str string, start, end int) string
Slice a string by rune.
Start must satisfy 0 <= start <= rune length.
End can be positive, zero or negative. If end >= 0, start and end must satisfy start <= end <= rune length. If end < 0, it means slice to the end of string.
Otherwise, Slice will panic as out of range.
func Squeeze(str, pattern string) string
Squeeze deletes adjacent repeated runes in str. If pattern is not empty, only runes matching the pattern will be squeezed.
Samples:
Squeeze("hello", "") => "helo"
Squeeze("hello", "m-z") => "hello"
Squeeze("hello world", " ") => "hello world"
func Successor(str string) string
Successor returns the successor to string.
If there is one alphanumeric rune is found in string, increase the rune by 1. If increment generates a "carry", the rune to the left of it is incremented. This process repeats until there is no carry, adding an additional rune if necessary.
If there is no alphanumeric rune, the rightmost rune will be increased by 1 regardless whether the result is a valid rune or not.
Only following characters are alphanumeric.
Samples (borrowed from ruby's String#succ document):
"abcd" => "abce" "THX1138" => "THX1139" "<<koala>>" => "<<koalb>>" "1999zzz" => "2000aaa" "ZZZ9999" => "AAAA0000" "***" => "**+"
func SwapCase(str string) string
SwapCase will swap characters case from upper to lower or lower to upper.
func ToCamelCase(str string) string
ToCamelCase is to convert words separated by space, underscore and hyphen to camel case.
Some samples.
"some_words" => "SomeWords" "http_server" => "HttpServer" "no_https" => "NoHttps" "_complex__case_" => "_Complex_Case_" "some words" => "SomeWords"
func ToKebabCase(str string) string
ToKebabCase can convert all upper case characters in a string to kebab case format.
Some samples.
"FirstName" => "first-name" "HTTPServer" => "http-server" "NoHTTPS" => "no-https" "GO_PATH" => "go-path" "GO PATH" => "go-path" // space is converted to '-'. "GO-PATH" => "go-path" // hyphen is converted to '-'. "http2xx" => "http-2xx" // insert an underscore before a number and after an alphabet. "HTTP20xOK" => "http-20x-ok" "Duration2m3s" => "duration-2m3s" "Bld4Floor3rd" => "bld4-floor-3rd"
func ToSnakeCase(str string) string
ToSnakeCase can convert all upper case characters in a string to snake case format.
Some samples.
"FirstName" => "first_name" "HTTPServer" => "http_server" "NoHTTPS" => "no_https" "GO_PATH" => "go_path" "GO PATH" => "go_path" // space is converted to underscore. "GO-PATH" => "go_path" // hyphen is converted to underscore. "http2xx" => "http_2xx" // insert an underscore before a number and after an alphabet. "HTTP20xOK" => "http_20x_ok" "Duration2m3s" => "duration_2m3s" "Bld4Floor3rd" => "bld4_floor_3rd"
func Translate(str, from, to string) string
Translate str with the characters defined in from replaced by characters defined in to.
From and to are patterns representing a set of characters. Pattern is defined as following.
Special characters:
Normal character represents itself, e.g. "abc" is a set including 'a', 'b' and 'c'.
Translate will try to find a 1:1 mapping from from to to. If to is smaller than from, last rune in to will be used to map "out of range" characters in from.
Note that '^' only works in the from pattern. It will be considered as a normal character in the to pattern.
If the to pattern is an empty string, Translate works exactly the same as Delete.
Samples:
Translate("hello", "aeiou", "12345") => "h2ll4"
Translate("hello", "a-z", "A-Z") => "HELLO"
Translate("hello", "z-a", "a-z") => "svool"
Translate("hello", "aeiou", "*") => "h*ll*"
Translate("hello", "^l", "*") => "**ll*"
Translate("hello ^ world", `\^lo`, "*") => "he*** * w*r*d"
func Width(str string) int
Width returns string width in monotype font. Multi-byte characters are usually twice the width of single byte characters.
Algorithm comes from `mb_strwidth` in PHP. http://php.net/manual/en/function.mb-strwidth.php
func WordCount(str string) int
WordCount returns number of words in a string.
Word is defined as a locale dependent string containing alphabetic characters, which may also contain but not start with `'` and `-` characters.
func WordSplit(str string) []string
WordSplit splits a string into words. Returns a slice of words. If there is no word in a string, return nil.
Word is defined as a locale dependent string containing alphabetic characters, which may also contain but not start with `'` and `-` characters.
Translator can translate string with pre-compiled from and to patterns. If a from/to pattern pair needs to be used more than once, it's recommended to create a Translator and reuse it.
type Translator struct {
// contains filtered or unexported fields
}
func NewTranslator(from, to string) *Translator
NewTranslator creates new Translator through a from/to pattern pair.
func (tr *Translator) HasPattern() bool
HasPattern returns true if Translator has one pattern at least.
func (tr *Translator) Translate(str string) string
Translate str with a from/to pattern pair.
See comment in Translate function for usage and samples.
func (tr *Translator) TranslateRune(r rune) (result rune, translated bool)
TranslateRune return translated rune and true if r matches the from pattern. If r doesn't match the pattern, original r is returned and translated is false.