rx

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rx

Expressive regex builder

Documentation

Overview

Package rx provides an expressive way to build regular expressions.

Index

• type Flags
• type Regex
  • func (r Regex) AnyOf(rxs ...Regex) Regex
  • func (r Regex) Capture(rxs ...Regex) Regex
  • func (r Regex) CaptureName(name string, rxs ...Regex) Regex
  • func (r Regex) In(rxs ...Regex) Regex
  • func (r Regex) NOrMore(n int, rx Regex) Regex
  • func (r Regex) NOrMoreLazy(n int, rx Regex) Regex
  • func (r Regex) NTimes(n int, rx Regex) Regex
  • func (r Regex) NTimesLazy(n int, rx Regex) Regex
  • func (r Regex) NUpToM(n, m int, rx Regex) Regex
  • func (r Regex) NUpToMLazy(n, m int, rx Regex) Regex
  • func (r Regex) NotIn(rxs ...Regex) Regex
  • func (r Regex) OneOrMore(rx Regex) Regex
  • func (r Regex) OneOrMoreLazy(rx Regex) Regex
  • func (r Regex) Then(rxs ...Regex) Regex
  • func (r Regex) WithFlags(flags Flags, rxs ...Regex) Regex
  • func (r Regex) ZeroOrMore(rx Regex) Regex
  • func (r Regex) ZeroOrMoreLazy(rx Regex) Regex
  • func (r Regex) ZeroOrOne(rx Regex) Regex
  • func (r Regex) ZeroOrOneLazy(rx Regex) Regex

Examples

• Regex.AnyOf
• Regex.Capture
• Regex.CaptureName
• Regex.In
• Regex.NOrMore
• Regex.NOrMoreLazy
• Regex.NTimes
• Regex.NTimesLazy
• Regex.NUpToM
• Regex.NUpToMLazy
• Regex.NotIn
• Regex.OneOrMore
• Regex.OneOrMoreLazy
• Regex.Then
• Regex.WithFlags
• Regex.ZeroOrMore
• Regex.ZeroOrMoreLazy
• Regex.ZeroOrOne
• Regex.ZeroOrOneLazy

Types

type Flags

type Flags uint

Flags changes the meaning of the regex.

const (
	// CaseInsensitive makes the regex case insensitive (flag "i" set).
	CaseInsensitive Flags = 1 << iota

	// CaseSensitive makes the regex case sensitive (flag "i" cleared,
	// default behavior).
	CaseSensitive

	// MultiLine makes StartOfText and EndOfText match the beginning and
	// the end of each line (flag "m" set).
	MultiLine

	// SingleLine makes StartOfText and EndOfText match the beginning and
	// the end of the whole text (flag "m" cleared, default behavior).
	SingleLine

	// AnyNL makes Any match new lines(flag "s" set).
	AnyNL

	// AnyNoNL makes Any not match new lines (flag "s" cleared, default
	// behavior).
	AnyNoNL

	// Ungreedy makes the quantifiers match the shortest text possible
	// (flag "U" set).
	Ungreedy

	// Greedy makes the quantifiers match the longest text possible (flag
	// "U" cleared, default behavior).
	Greedy
)

type Regex

type Regex string

Regex represents a regular expression.

const (
	// Any matches any character (".").
	Any Regex = "."
)

func (Regex) AnyOf

func (r Regex) AnyOf(rxs ...Regex) Regex

AnyOf appends an alternative to the regex. The resulting alternative matches any of the given regexes.

Example

fmt.Println(Regex("a").AnyOf("b", "c"))

Output:

a(?:b|c)

func (Regex) Capture

func (r Regex) Capture(rxs ...Regex) Regex

Capture appends a capture group to the regexes. The regexes given as arguments are just concatenated.

Example

fmt.Println(Regex("a").Capture("a", "b"))

Output:

a(ab)

func (Regex) CaptureName

func (r Regex) CaptureName(name string, rxs ...Regex) Regex

CaptureName appends a named capture group to the regexes. The regexes given as arguments are just concatenated.

Example

fmt.Println(Regex("a").CaptureName("foo", "a", "b"))

Output:

a(?P<foo>ab)

func (Regex) In

func (r Regex) In(rxs ...Regex) Regex

In generates a character class composed by the concatenation of all arguments.

Example

fmt.Println(Regex("a").In("0-9", "a-z"))

Output:

a[0-9a-z]

func (Regex) NOrMore

func (r Regex) NOrMore(n int, rx Regex) Regex

NOrMore appends the given regex with an minimum number of repeats ("{N,}"), prefer more.

Example

fmt.Println(Regex("a").NOrMore(3, "b"))
fmt.Println(Regex("a").NOrMore(3, "abc"))

Output:

ab{3,}
a(?:abc){3,}

func (Regex) NOrMoreLazy

func (r Regex) NOrMoreLazy(n int, rx Regex) Regex

NOrMoreLazy appends the given regex with an minimum number of repeats ("{N,}"), prefer more.

Example

fmt.Println(Regex("a").NOrMoreLazy(3, "b"))
fmt.Println(Regex("a").NOrMoreLazy(3, "abc"))

Output:

ab{3,}?
a(?:abc){3,}?

func (Regex) NTimes

func (r Regex) NTimes(n int, rx Regex) Regex

NTimes appends the given regex with an exact number of repeats ("{N}").

Example

fmt.Println(Regex("a").NTimes(3, "b"))
fmt.Println(Regex("a").NTimes(3, "abc"))

Output:

ab{3}
a(?:abc){3}

func (Regex) NTimesLazy

func (r Regex) NTimesLazy(n int, rx Regex) Regex

NTimesLazy appends the given regex with an exact number of repeats ("{N}").

Example

fmt.Println(Regex("a").NTimesLazy(3, "b"))
fmt.Println(Regex("a").NTimesLazy(3, "abc"))

Output:

ab{3}?
a(?:abc){3}?

func (Regex) NUpToM

func (r Regex) NUpToM(n, m int, rx Regex) Regex

NUpToM appends the given regex with an minimum and maximum number of repeats ("{N,M}"), prefer more.

Example

fmt.Println(Regex("a").NUpToM(3, 5, "b"))
fmt.Println(Regex("a").NUpToM(3, 5, "abc"))

Output:

ab{3,5}
a(?:abc){3,5}

func (Regex) NUpToMLazy

func (r Regex) NUpToMLazy(n, m int, rx Regex) Regex

NUpToMLazy appends the given regex with an minimum and maximum number of repeats ("{N,M}"), prefer more.

Example

fmt.Println(Regex("a").NUpToMLazy(3, 5, "b"))
fmt.Println(Regex("a").NUpToMLazy(3, 5, "abc"))

Output:

ab{3,5}?
a(?:abc){3,5}?

func (Regex) NotIn

func (r Regex) NotIn(rxs ...Regex) Regex

NotIn generates a negated character class composed by the concatenation of all arguments.

Example

fmt.Println(Regex("a").NotIn("0-9", "a-z"))

Output:

a[^0-9a-z]

func (Regex) OneOrMore

func (r Regex) OneOrMore(rx Regex) Regex

OneOrMore appends the given regex with a "one or more" quantifier ("+"), prefer more.

Example

fmt.Println(Regex("a").OneOrMore("b"))
fmt.Println(Regex("a").OneOrMore("abc"))

Output:

ab+
a(?:abc)+

func (Regex) OneOrMoreLazy

func (r Regex) OneOrMoreLazy(rx Regex) Regex

OneOrMoreLazy appends the given regex with a "one or more" quantifier ("+"), prefer more.

Example

fmt.Println(Regex("a").OneOrMoreLazy("b"))
fmt.Println(Regex("a").OneOrMoreLazy("abc"))

Output:

ab+?
a(?:abc)+?

func (Regex) Then

func (r Regex) Then(rxs ...Regex) Regex

Then appends the given regexes to the current one.

Example

fmt.Println(Regex("a").Then("b", Any))

Output:

ab.

func (Regex) WithFlags

func (r Regex) WithFlags(flags Flags, rxs ...Regex) Regex

WithFlags appends a non-capturing group with the given flags set to the regex. The regexes given as arguments are just concatenated.

Example

fmt.Println(Regex("a").WithFlags(AnyNL|CaseSensitive, "a", "b"))

Output:

a(?s-i:ab)

func (Regex) ZeroOrMore

func (r Regex) ZeroOrMore(rx Regex) Regex

ZeroOrMore appends the given regex with a "zero or more" quantifier ("*"), prefer more.

Example

fmt.Println(Regex("a").ZeroOrMore("b"))
fmt.Println(Regex("a").ZeroOrMore("abc"))

Output:

ab*
a(?:abc)*

func (Regex) ZeroOrMoreLazy

func (r Regex) ZeroOrMoreLazy(rx Regex) Regex

ZeroOrMoreLazy appends the given regex with a "zero or more" quantifier ("*"), prefer more.

Example

fmt.Println(Regex("a").ZeroOrMoreLazy("b"))
fmt.Println(Regex("a").ZeroOrMoreLazy("abc"))

Output:

ab*?
a(?:abc)*?

func (Regex) ZeroOrOne

func (r Regex) ZeroOrOne(rx Regex) Regex

ZeroOrOne appends the given regex with a "one or more" quantifier ("?"), prefer more.

Example

fmt.Println(Regex("a").ZeroOrOne("b"))
fmt.Println(Regex("a").ZeroOrOne("abc"))

Output:

ab?
a(?:abc)?

func (Regex) ZeroOrOneLazy

func (r Regex) ZeroOrOneLazy(rx Regex) Regex

ZeroOrOneLazy appends the given regex with a "one or more" quantifier ("?"), prefer more.

Example

fmt.Println(Regex("a").ZeroOrOneLazy("b"))
fmt.Println(Regex("a").ZeroOrOneLazy("abc"))

Output:

ab??
a(?:abc)??