package meg

import "github.com/multiformats/go-multiaddr/x/meg"

package meg implements Regular Expressions for multiaddr Components. It's short for "Megular Expressions"

Index ¶

• Variables
• func Match[L ListOfMatchable](matcher Matcher, components L) (bool, error)
• type CaptureFunc
• type ListOfMatchable
• type MatchState
• func (s MatchState) String() string
• type Matchable
• type Matcher
• func PatternToMatcher(patterns ...Pattern) Matcher
• func (s Matcher) String() string
• type Pattern
• func CaptureBytes(code int, val *[]byte) Pattern
• func CaptureOneOrMoreBytes(code int, vals *[][]byte) Pattern
• func CaptureOneOrMoreStrings(code int, vals *[]string) Pattern
• func CaptureString(code int, val *string) Pattern
• func CaptureWithF(code int, f CaptureFunc) Pattern
• func CaptureZeroOrMoreBytes(code int, vals *[][]byte) Pattern
• func CaptureZeroOrMoreStrings(code int, vals *[]string) Pattern
• func CaptureZeroOrMoreWithF(code int, f CaptureFunc) Pattern
• func Cat(patterns ...Pattern) Pattern
• func OneOrMore(code int) Pattern
• func Optional(s Pattern) Pattern
• func Or(p ...Pattern) Pattern
• func Val(code int) Pattern
• func ZeroOrMore(code int) Pattern

Variables ¶

var Any int = matchAny

Any is a special code that matches any value.

Functions ¶

func Match ¶

func Match[L ListOfMatchable](matcher Matcher, components L) (bool, error)

Match returns whether the given Components match the Matcher

Errors are used to communicate capture errors. If the error is non-nil the returned bool will be false.

Components must be a ListOfMatchable to allow us to use a slice of []T as a []Matchable when *T implements Matchable.

Types ¶

type CaptureFunc ¶

type CaptureFunc func(Matchable) error

type ListOfMatchable ¶

type ListOfMatchable interface {
	Get(i int) Matchable
	Len() int
}

ListOfMatchable is anything list-like that contains Matchable items. This allows us to convert a slice of []T as a []Matchable when *T implements Matchable. In the future, this may not be required if Go generics allows us to say S ~[]T, and *T implements Matchable. This may also not be required if we move this out of its own package and depend on Multiaddr and Components directly.

type MatchState ¶

type MatchState struct {
	// contains filtered or unexported fields
}

MatchState is the Thompson NFA for a regular expression.

func (MatchState) String ¶

func (s MatchState) String() string

type Matchable ¶

type Matchable interface {
	Code() int
	// Value() returns the string representation of the matchable.
	Value() string
	// RawValue() returns the byte representation of the Value
	RawValue() []byte
	// Bytes() returns the underlying bytes of the matchable. For multiaddr
	// Components, this includes the protocol code and possibly the varint
	// encoded size.
	Bytes() []byte
}

Matchable is an interface for any thing that can be matched against by this package. In the future, we may use multiaddr.Component types directly.

type Matcher ¶

type Matcher struct {
	// contains filtered or unexported fields
}

Matcher holds a graph of match state nodes. Use PatternToMatcher to create.

func PatternToMatcher ¶

func PatternToMatcher(patterns ...Pattern) Matcher

func (Matcher) String ¶

func (s Matcher) String() string

type Pattern ¶

type Pattern = func(states []MatchState, nextIdx int) ([]MatchState, int)

Pattern is a curried MatchState. Given the slice of current MatchStates and a handle (int index) to the next MatchState, it returns a (possibly modified) slice of next MatchStates and handle to the inserted MatchState.

func CaptureBytes ¶

func CaptureBytes(code int, val *[]byte) Pattern

func CaptureOneOrMoreBytes ¶

func CaptureOneOrMoreBytes(code int, vals *[][]byte) Pattern

func CaptureOneOrMoreStrings ¶

func CaptureOneOrMoreStrings(code int, vals *[]string) Pattern

func CaptureString ¶

func CaptureString(code int, val *string) Pattern

func CaptureWithF ¶

func CaptureWithF(code int, f CaptureFunc) Pattern

func CaptureZeroOrMoreBytes ¶

func CaptureZeroOrMoreBytes(code int, vals *[][]byte) Pattern

func CaptureZeroOrMoreStrings ¶

func CaptureZeroOrMoreStrings(code int, vals *[]string) Pattern

func CaptureZeroOrMoreWithF ¶

func CaptureZeroOrMoreWithF(code int, f CaptureFunc) Pattern

func Cat ¶

func Cat(patterns ...Pattern) Pattern

func OneOrMore ¶

func OneOrMore(code int) Pattern

func Optional ¶

func Optional(s Pattern) Pattern

func Or ¶

func Or(p ...Pattern) Pattern

func Val ¶

func Val(code int) Pattern

func ZeroOrMore ¶

func ZeroOrMore(code int) Pattern

Source Files ¶

meg.go sugar.go