README
¶
strutils
Additional string parsing and manipulation functions for Go.
Comparisons, prefixes, trimming, quoting, wildcards, random, segmentation, tags, values, wrapping, conversion, printing.
Uses unsafe package.
Status
Ever evolving.
License
MIT.
See included LICENSE file.
Documentation
¶
Overview ¶
Package strings adds additional string utility functions.
Index ¶
- Variables
- func CamelCase(s string) string
- func Compare(a, b string) int
- func CompareFold(a, b string) int
- func FetchLeft(s, sep string) string
- func FetchLeftFold(s, sep string) string
- func FetchRight(s, sep string) string
- func FetchRightFold(s, sep string) string
- func HasPrefixFold(s, prefix string) bool
- func HasSuffixFold(s, suffix string) bool
- func IndexFold(s, substr string) int
- func Indexes(s, sep string) (r []int)
- func IndexesFold(s, sep string) []int
- func IsAlphanumeric(c byte) bool
- func IsDigit(c byte) bool
- func IsLetter(c byte) bool
- func IsLower(c byte) bool
- func IsUpper(c byte) bool
- func KebabCase(s string) string
- func LookupTag(rawStructTag, key string) (value string, ok bool)
- func MatchesWildcard(text, pattern string) bool
- func PascalCase(s string) string
- func QuoteDouble(s string) string
- func QuoteSingle(s string) string
- func Random(set []byte) string
- func RandomByte(set []byte) []byte
- func RandomLower() string
- func RandomLowers(length int) string
- func RandomNum() string
- func RandomNums(length int) string
- func RandomSpecial() string
- func RandomSpecials(length int) string
- func RandomString(lo, up, nums bool, length int) string
- func RandomUpper() string
- func RandomUppers(length int) string
- func Randoms(set []byte, length int) string
- func Segment(s, sep string, start int) (segment string, next int)
- func SegmentFold(s, sep string, start int) (segment string, next int)
- func SnakeCase(s string) string
- func ToLower(c byte) byte
- func ToUpper(c byte) byte
- func Unique(in ...string) (out []string)
- func UnquoteDouble(s string) (string, bool)
- func UnquoteSingle(s string) (string, bool)
- func UnsafeString(b []byte) string
- func UnsafeStringBytes(s string) []byte
- func Unwrap(s, prefix, suffix string) (string, bool)
- func UnwrapFold(s, prefix, suffix string) (string, bool)
- func Wrap(s, prefix, suffix string) string
- func WrapText(text string, cols int, force bool) (out []string)
- type CaseMapping
- type Converter
- type Foo
- type PairKey
- type StringValueGetter
- type StringValueSetter
- type Tag
- type TagKey
- type Values
- func (self Values) Add(key string, values ...string)
- func (self Values) Clear()
- func (self Values) Exists(key string) (exists bool)
- func (self Values) ExistsNonEmpty(key string) (exists bool)
- func (self Values) First(key string) (s string)
- func (self Values) Set(key string, out *string) (exists bool)
Constants ¶
This section is empty.
Variables ¶
var ( Wovels = "aeiou" Consonants = "bcdfghjklmnpqrstvxyz" SpecialChars = " !\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~" Numerals = "0123456789" AlphaUpper = "ABCDEFGHIJKLMNOPQRSTUVXYZ" AlphaLower = "abcdefghijklmnopqrstuvxyz" Alpha = AlphaUpper + AlphaLower AlphaNumerals = Numerals + Alpha )
var ( WovelsBytes = []byte(Wovels) ConsonantsBytes = []byte(Consonants) SpecialCharsBytes = []byte(SpecialChars) NumeralsBytes = []byte(Numerals) AlphaUpperBytes = []byte(AlphaUpper) AlphaLowerBytes = []byte(AlphaLower) AlphaBytes = []byte(Alpha) AlphaNumeralsBytes = []byte(AlphaNumerals) )
var ErrTagNotFound = errors.New("tag not found")
ErrTagNotFound is returned when tag named [Tag.TagKey] was not found in a tag string literal.
Functions ¶
func CompareFold ¶
CompareFold returns 1 if a > b, -1 if a < b or 0 if a == b. Comparison is not case-sensitive.
func FetchLeft ¶
Return s prefix up to sep starting from the left. If sep not found returns an empty string.
func FetchLeftFold ¶
Return s prefix up to sep starting from the left. Separator search is case-insesitive, result casing is not modified. If sep not found returns an empty string.
func FetchRight ¶
Return s suffix up to sep starting from the right. If sep not found returns an empty string.
func FetchRightFold ¶
Return s suffix up to sep starting from the right. Separator search is case-insesitive, result casing is not modified. If sep not found returns an empty string.
func HasPrefixFold ¶
HasPrefixFold tests whether the string s begins with prefix. Case-insensitive.
func HasSuffixFold ¶
HasSuffixFold tests whether the string s ends with suffix Case-insensitive.
func IndexFold ¶
IndexFold returns the index of the first instance of substr in s, or -1 if substr is not present in s. Search is case-insensitive.
func Indexes ¶
Indexes returns a slice of all indexes of "sep" starting byte positions in "s", or an empty slice if none are present in "s".
func IndexesFold ¶
Indexes returns a slice of all indexes of "sep" starting byte positions in "s", or an empty slice if none are present in "s". Case-insensitive.
func IsAlphanumeric ¶
IsAlphanumeric returns true if c is a digit, lower or upper alpha.
func LookupTag ¶
LookupTag returns the value associated with key in the tag string. If the key is present in the tag the value (which may be empty) is returned. Otherwise the returned value will be the empty string. The ok return value reports whether the value was explicitly set in the tag string. If the tag does not have the conventional format, the value returned by LookupTag is unspecified.
LookupTag is a copy of (reflect.Lookup) to skip the reflect include.
func MatchesWildcard ¶
Matches "text" against "pattern". Case insensitive. Returns truth. * matches any number of characters. ? matches one character.
func RandomByte ¶
Random returns a string containing a single character from set.
func RandomLowers ¶
Returns a string of random lowercase letters of length.
func RandomSpecial ¶
func RandomSpecial() string
Returns a string containing a random password special character.
func RandomSpecials ¶
Returns a string of random special characters of length.
func RandomString ¶
Returns a random string of "length". If "lo" includes lowercase letters. If "up" includes uppercase letters. If "num" includes numbers.
func RandomUppers ¶
Returns a string of random uppercase letters of length.
func Segment ¶
Segment returns the word up to the next separator and index of s just after the separator. Scan of s starts at start index.
If sep was not found returns s starting at start and -1. If the end of s was reached resulting next will be -1. Returns an empty string and -1 if start is out of range or sep is empty.
func SegmentFold ¶
SegmentFold is the case-insensitive version of Segment.
func UnquoteDouble ¶
UnquoteDouble removes double quotes around s and returns it and true on success. If either leading or trailing quote is not found result is s, false.
func UnquoteSingle ¶
UnquoteSingle removes single quotes around s and returns it and true on success. If either leading or trailing quote is not found result is s, false.
func UnsafeString ¶
UnsafeString performs unholy acts to avoid allocations https://github.com/kubernetes/kubernetes/blob/e4b74dd12fa8cb63c174091d5536a10b8ec19d34/staging/src/k8s.io/apiserver/pkg/authentication/token/cache/cached_token_authenticator.go#L288-L297
func UnsafeStringBytes ¶
UnsafeStringBytes returns bytes of a string without allocating a slice.
Result is a weak, non-garbage collected byte slice that is valid for the lifetime of s.
func Unwrap ¶
Unwrap unpacks the string by removing prefix and suffix. If both prefix and suffix were found result is an unpacked string and true else result is s and false. Both prefix and suffix are optional and can be empty in which case their removal is not performed.
func UnwrapFold ¶
UnwrapFold is the case-insensitive version of Unpack.
func WrapText ¶
WrapText wraps text into multiple lines at first whitespace before or exactly at cols.
If a word is longer than cols and force is true it is split at cols length regardless of white space. If force is false, the word is not split and placed into its own line at first next whitespace.
Allocates runes of text and appends to out without preallocation.
Types ¶
type CaseMapping ¶
type CaseMapping int
CaseMapping specifies one of case mapping supported by this package.
const ( // InvalidMapping is the invalid/undefined mapping. InvalidMapping CaseMapping = iota // NoMapping specifies no mapping. NoMapping // PascalMapping specifies PascalCase mapping. PascalMapping // SnakeMapping specifies snake_case mapping. SnakeMapping // CamelMapping specifies camelCase mapping. CamelMapping // KebabMapping specifies kebab-case mapping. KebabMapping )
func (CaseMapping) Map ¶
func (self CaseMapping) Map(s string) string
Map case maps s depending on self value. If mapping value is unknown input string is returned unmodified.
func (CaseMapping) MarshalText ¶
func (self CaseMapping) MarshalText() (text []byte, err error)
MarshalText implementes encoding.TextMarshaler on CaseMapping.
func (CaseMapping) String ¶
func (self CaseMapping) String() string
String implements stringer on CaseMapping.
func (*CaseMapping) UnmarshalText ¶
func (self *CaseMapping) UnmarshalText(text []byte) error
UnmarshalText implementes encoding.TextUnmarshaler on CaseMapping.
type Converter ¶
type Converter struct {
// TimeFormat is the time layout sring used to parse time strings.
TimeFormat string
}
Converter converts strings and string slices into basic go types.
func NewConverter ¶
func NewConverter() Converter
NewConverter returns a new Converter with default values.
func (Converter) StringToAny ¶
StringToAny converts in to out or returns an error.
In must be a GoString compatible with out which must be a pointer to the variable whose value is to be set. Basic, non-structured types and slices of those types are supported.
type Foo ¶
type Foo struct {
// MinName is the minimum length for various name generation functions.
MinName int
// MaxName is the maximum length for various name generation functions.
MaxName int
// Domains is a set of domains used for generating fake urls or emails.
Domains []string
}
Foo returns various random texts.
type PairKey ¶
type PairKey = string
PairKey is a recognized key in a set of key=value pairs parsed from a tag value.
Given:
tagKey := "foo" pairKey := "key1" rawTag := `json:"omitempty" foo:"key1,key2=value1,key2=value2,key3"`
pairKey specifies the "key1" inside a value keyed by tagKey.
type StringValueGetter ¶
type StringValueGetter interface {
Get() string
}
StringValueGetter is an interface which can return self as string.
type StringValueSetter ¶
StringValueSetter is an interface which can convert a string to self.
type Tag ¶
type Tag struct {
// TagKey is the name of the tag whose value is to be parsed into [Values].
TagKey
// Separator is the pair separator.
//
// Defaults to comma ",".
Separator string
// KnownPairKeys is a set of recognised pair keys found inside a value of
// a tag.
//
// If it is an empty slice all keys or key=value pairs will be parsed.
// If it is not an empty slice, unrecognised keys will be skipped silently
// or an error will be thrown if [Tag.ErrorOnUnknownKey] is true.
KnownPairKeys []PairKey
// ErrorOnUnknownKey, if true will make parse functions throw an error if
// an unrecognised tag is found and [Tag.Keys] is not an empty slice.
//
// Default: false
ErrorOnUnknownKey bool
// Raw is the raw tag value that was parsed.
// Set after [Tag.Parse].
Raw string
// Values are the parsed values. Values are nil until [Tag.ParseDocs] or
// [Tag.ParseStructTag] is called.
Values
}
Tag parses value of a key inside a tag string literal into Values map.
Given:
tag := `json:"omitempty" MyTag:"key1,key2=value1,key2=value2,key3"`
Results in following Values structure:
Values{
"key1": nil,
"key2": []string{
"value1",
"value2",
}
"key3": nil,
}
The following rules, equal to how Go parses tags apply:
Keys may appear without values or in key=value format. Multiple keys or pairs are separated by a comma. Values may not contain commas or double quotes.
Leading and trailing space is trimmed from pair values. Specifying a pair with the same key multiple times adds values to an entry under key in parsed Values.
Specifying a PairKey without a value adds an entry without values in the Values map. Specifying a PairKey with an empty value multiple times is a no-op.
See Tag.Parse for details.
type TagKey ¶
type TagKey = string
TagKey names a key inside a tag string literal whose value is to be parsed into Values.
Given:
tagKey := "foo" rawTag := `json:"omitempty" foo:"key1,key2=value1,key2=value2,key3"`
TagKey specifies the "foo" key inside a tag string literal.
type Values ¶
Values is a map of parsed key=value pairs from a tag value.
func (Values) Add ¶
Add appends values to value slice under key.
If no values exist under key a new entry is added. If no values were specified target slice is unmodified. Initial value of an empty entry is a nil slice.
func (Values) ExistsNonEmpty ¶
Exists returns true if entry under key exists and has at least one value which is not empty.
func (Values) First ¶
First returns the first value keyed under key. If entry not found or no values for entry found returns an empty string. Use Values.Exists to check if an entry exists.
Source Files