isa

type Any ¶

type Any struct {
	N byte
	// contains filtered or unexported fields
}

Any consumes the next N bytes and fails if that is not possible.

func (i Any) String() string

type BackCommit ¶

type BackCommit struct {
	Lbl Label
	// contains filtered or unexported fields
}

BackCommit pops a backtrack entry off the stack, goes to the subject position in the entry, and jumps to Lbl.

func (i BackCommit) String() string

type BackReference ¶

type BackReference struct {
	Symbols map[int]string
}

func NewBackRef() *BackReference

func (r *BackReference) Check(b []byte, src *input.Input, id, flag int) int

type Call ¶

type Call struct {
	Lbl Label
	// contains filtered or unexported fields
}

Call pushes the next instruction to the stack as a return address and jumps to Lbl.

func (i Call) String() string

type CaptureBegin ¶

type CaptureBegin struct {
	Id int
	// contains filtered or unexported fields
}

CaptureBegin begins capturing the given ID.

func (i CaptureBegin) String() string

type CaptureEnd ¶

type CaptureEnd struct {
	Id int
	// contains filtered or unexported fields
}

CaptureEnd completes an active capture.

func (i CaptureEnd) String() string

type CaptureFull ¶

type CaptureFull struct {
	Back byte
	Id   int
	// contains filtered or unexported fields
}

CaptureFull begins a capture for the given ID at the current subject position minus Back, and immediately completes the capture. This is equivalent to CaptureLate Back ID; CaptureEnd.

func (i CaptureFull) String() string

type CaptureLate ¶

type CaptureLate struct {
	Back byte
	Id   int
	// contains filtered or unexported fields
}

CaptureLate begins capturing the given ID at the current subject position minus Back.

func (i CaptureLate) String() string

type Char ¶

type Char struct {
	Byte byte
	// contains filtered or unexported fields
}

Char consumes the next byte of the subject if it matches Byte and fails otherwise.

func (i Char) String() string

type CheckBegin ¶

type CheckBegin struct {
	Id   int
	Flag int
	// contains filtered or unexported fields
}

CheckBegin marks the beginning position for a checker.

func (i CheckBegin) String() string

type CheckEnd ¶

type CheckEnd struct {
	Checker Checker
	// contains filtered or unexported fields
}

CheckEnd records the end position of a checker and applies the checker to determine if the match should fail.

func (i CheckEnd) String() string

type Checker ¶

type Checker interface {
	Check(b []byte, src *input.Input, id, flag int) int
}

A Checker is used so the user can perform additional custom validation of parse results. For example, you might want to parse only 8-bit integers by matching [0-9]+ and then using a checker to ensure the matched integer is in the range 0-256.

type Choice ¶

type Choice struct {
	Lbl Label
	// contains filtered or unexported fields
}

Choice pushes Lbl to the stack and if there is a failure the label will be popped from the stack and jumped to.

func (i Choice) String() string

type Commit ¶

type Commit struct {
	Lbl Label
	// contains filtered or unexported fields
}

Commit jumps to Lbl and removes the top entry from the stack

func (i Commit) String() string

type Empty ¶

type Empty struct {
	Op syntax.EmptyOp
	// contains filtered or unexported fields
}

Empty makes a zero-width assertion according to the Op option. We use the same zero-width assertions that are supported by Go's regexp package.

func (i Empty) String() string

type End ¶

type End struct {
	Fail bool
	// contains filtered or unexported fields
}

End immediately completes the pattern as a match.

func (i End) String() string

type Error ¶

type Error struct {
	Message string
	// contains filtered or unexported fields
}

Error logs an error message at the current position.

func (i Error) String() string

type Fail ¶

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

Fail causes the instruction pointer to go to the fail state.

func (i Fail) String() string

type FailTwice ¶

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

FailTwice pops an entry off the stack and sets the instruction pointer to the fail state.

func (i FailTwice) String() string

type Insn ¶

type Insn interface {
	// contains filtered or unexported methods
}

Insn represents the interface for an instruction in the ISA

type Jump ¶

type Jump struct {
	Lbl Label
	// contains filtered or unexported fields
}

Jump jumps to Lbl.

func (i Jump) String() string

type JumpType ¶

type JumpType interface {
	// contains filtered or unexported methods
}

A JumpType instruction is any instruction that refers to a Label.

type Label ¶

type Label struct {
	Id int
	// contains filtered or unexported fields
}

Label is used for marking a location in the instruction code with a unique ID

func NewLabel() Label

func (i Label) String() string

type MapChecker ¶

type MapChecker map[string]struct{}

func NewMapChecker(strs []string) MapChecker

func (m MapChecker) Check(b []byte, src *input.Input, id, flag int) int

type MemoClose ¶

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

MemoClose completes a memoization entry and adds the entry into the memo table if it meets certain conditions (size, or other heuristics).

func (i MemoClose) String() string

type MemoOpen ¶

type MemoOpen struct {
	Lbl Label
	Id  int
	// contains filtered or unexported fields
}

MemoOpen begins a memo entry at this position. It marks the pattern that is being memoized with a unique ID for that pattern, and stores a label to jump to if the pattern is found in the memoization table.

func (i MemoOpen) String() string

type MemoTree ¶

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

MemoTree "tree-ifies" the current memoization entries on the stack.

func (i MemoTree) String() string

type MemoTreeClose ¶

type MemoTreeClose struct {
	Id int
	// contains filtered or unexported fields
}

MemoTreeClose completes the tree memoization routine.

func (i MemoTreeClose) String() string

type MemoTreeInsert ¶

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

MemoTreeInsert performs insertion into the memoization table for the tree memoization strategy.

func (i MemoTreeInsert) String() string

type MemoTreeOpen ¶

type MemoTreeOpen struct {
	Lbl Label
	Id  int
	// contains filtered or unexported fields
}

MemoTreeOpen starts a memoization tree repetition routine.

func (i MemoTreeOpen) String() string

type Nop ¶

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

Nop does nothing.

func (i Nop) String() string

type PartialCommit ¶

type PartialCommit struct {
	Lbl Label
	// contains filtered or unexported fields
}

PartialCommit modifies the backtrack entry on the top of the stack to point to the current subject offset, and jumps to Lbl.

func (i PartialCommit) String() string

type Program ¶

type Program []Insn

A Program is a sequence of instructions

func (p Program) Size() int

func (p Program) String() string

type RefKind ¶

type RefKind uint8

const (
	RefDef RefKind = iota
	RefUse
	RefBlock
)

type Return ¶

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

Return pops a return address off the stack and jumps to it.

func (i Return) String() string

type Set ¶

type Set struct {
	Chars charset.Set
	// contains filtered or unexported fields
}

Set consumes the next byte of input if it is in the set of chars defined by Chars.

func (i Set) String() string

type Span ¶

type Span struct {
	Chars charset.Set
	// contains filtered or unexported fields
}

Span consumes zero or more bytes in the set Chars. This instruction never fails.

func (i Span) String() string

type TestAny ¶

type TestAny struct {
	N   byte
	Lbl Label
	// contains filtered or unexported fields
}

TestAny consumes the next N bytes and jumps to Lbl if that is not possible. If the consumption is possible, a backtrack entry referring to Lbl and the subject position from before consumption is pushed to the stack.

func (i TestAny) String() string

type TestChar ¶

type TestChar struct {
	Byte byte
	Lbl  Label
	// contains filtered or unexported fields
}

TestChar consumes the next byte if it matches Byte and jumps to Lbl otherwise. If the consumption is possible, a backtrack entry referring to Lbl and the subject position from before consumption is pushed to the stack.

func (i TestChar) String() string

type TestCharNoChoice ¶

type TestCharNoChoice struct {
	Byte byte
	Lbl  Label
	// contains filtered or unexported fields
}

TestCharNoChoice consumes the next byte if it matches Byte and jumps to Lbl otherwise. No backtrack entry is pushed to the stack.

func (i TestCharNoChoice) String() string

type TestSet ¶

type TestSet struct {
	Chars charset.Set
	Lbl   Label
	// contains filtered or unexported fields
}

TestSet consumes the next byte if it is in the set Chars and jumps to Lbl otherwise. If the consumption is possible, a backtrack entry referring to Lbl and the subject position from before consumption is pushed to the stack.

func (i TestSet) String() string

type TestSetNoChoice ¶

type TestSetNoChoice struct {
	Chars charset.Set
	Lbl   Label
	// contains filtered or unexported fields
}

TestSetNoChoice is the same as TestSet but no backtrack entry is pushed to the stack.

func (i TestSetNoChoice) String() string