47 lines
737 B
Go
47 lines
737 B
Go
package parsec
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import "fmt"
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type Node interface {
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Pos() int
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}
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type Token struct {
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pos int
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Value string
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}
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func (e Token) Pos() int { return e.pos }
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func NewToken(pos int, value string) Token {
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return Token{pos, value}
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}
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type Error struct {
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pos int
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Message string
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}
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func (e Error) Pos() int { return e.pos }
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func (e Error) Error() string { return fmt.Sprintf("offset %d: %s", e.pos, e.Message) }
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func NewError(pos int, message string) Error {
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return Error{pos, message}
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}
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func IsError(n Node) bool {
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_, isErr := n.(Error)
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return isErr
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}
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type Sequence struct {
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pos int
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Nodes []Node
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}
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func (e Sequence) Pos() int { return e.pos }
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func NewSequence(pos int, n ...Node) Sequence {
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return Sequence{pos, n}
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}
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