Golang Token.IsKeyword方法代码示例

// intersperseComments consumes all comments that appear before the next token
// tok and prints it together with the buffered whitespace (i.e., the whitespace
// that needs to be written before the next token). A heuristic is used to mix
// the comments and whitespace. The intersperseComments result indicates if a
// newline was written or if a formfeed was dropped from the whitespace buffer.
//
func (p *printer) intersperseComments(next token.Position, tok token.Token) (wroteNewline, droppedFF bool) {
	var last *ast.Comment
	for p.commentBefore(next) {
		for _, c := range p.comment.List {
			p.writeCommentPrefix(p.posFor(c.Pos()), next, last, c, tok.IsKeyword())
			p.writeComment(c)
			last = c
		}
		p.nextComment()
	}

	if last != nil {
		// if the last comment is a /*-style comment and the next item
		// follows on the same line but is not a comma or a "closing"
		// token, add an extra blank for separation
		if last.Text[1] == '*' && p.lineFor(last.Pos()) == next.Line && tok != token.COMMA &&
			tok != token.RPAREN && tok != token.RBRACK && tok != token.RBRACE {
			p.writeByte(' ', 1)
		}
		// ensure that there is a line break after a //-style comment,
		// before a closing '}' unless explicitly disabled, or at eof
		needsLinebreak :=
			last.Text[1] == '/' ||
				tok == token.RBRACE && p.mode&noExtraLinebreak == 0 ||
				tok == token.EOF
		return p.writeCommentSuffix(needsLinebreak)
	}

	// no comment was written - we should never reach here since
	// intersperseComments should not be called in that case
	p.internalError("intersperseComments called without pending comments")
	return
}

// intersperseComments consumes all comments that appear before the next token
// tok and prints it together with the buffered whitespace (i.e., the whitespace
// that needs to be written before the next token). A heuristic is used to mix
// the comments and whitespace. intersperseComments returns true if a pending
// formfeed was dropped from the whitespace buffer.
//
func (p *printer) intersperseComments(next token.Position, tok token.Token) (droppedFF bool) {
	var last *ast.Comment
	for ; p.commentBefore(next); p.cindex++ {
		for _, c := range p.comments[p.cindex].List {
			p.writeCommentPrefix(p.fset.Position(c.Pos()), next, last, tok.IsKeyword())
			p.writeComment(c)
			last = c
		}
	}

	if last != nil {
		if last.Text[1] == '*' && p.fset.Position(last.Pos()).Line == next.Line {
			// the last comment is a /*-style comment and the next item
			// follows on the same line: separate with an extra blank
			p.write([]byte{' '})
		}
		// ensure that there is a line break after a //-style comment,
		// before a closing '}' unless explicitly disabled, or at eof
		needsLinebreak :=
			last.Text[1] == '/' ||
				tok == token.RBRACE && p.mode&noExtraLinebreak == 0 ||
				tok == token.EOF
		return p.writeCommentSuffix(needsLinebreak)
	}

	// no comment was written - we should never reach here since
	// intersperseComments should not be called in that case
	p.internalError("intersperseComments called without pending comments")
	return false
}

// intersperseComments consumes all comments that appear before the next token
// tok and prints it together with the buffered whitespace (i.e., the whitespace
// that needs to be written before the next token). A heuristic is used to mix
// the comments and whitespace. intersperseComments returns true if a pending
// formfeed was dropped from the whitespace buffer.
//
func (p *printer) intersperseComments(next token.Position, tok token.Token) (droppedFF bool) {
	var last *ast.Comment
	for ; p.commentBefore(next); p.cindex++ {
		for _, c := range p.comments[p.cindex].List {
			p.writeCommentPrefix(c.Pos(), next, last == nil, tok.IsKeyword())
			p.writeComment(c)
			last = c
		}
	}

	if last != nil {
		if last.Text[1] == '*' && last.Pos().Line == next.Line {
			// the last comment is a /*-style comment and the next item
			// follows on the same line: separate with an extra blank
			p.write([]byte{' '})
		}
		// ensure that there is a newline after a //-style comment
		// or if we are before a closing '}' or at the end of a file
		return p.writeCommentSuffix(last.Text[1] == '/' || tok == token.RBRACE || tok == token.EOF)
	}

	// no comment was written - we should never reach here since
	// intersperseComments should not be called in that case
	p.internalError("intersperseComments called without pending comments")
	return false
}

func tokenclass(tok token.Token) int {
	switch {
	case tok.IsLiteral():
		return literal
	case tok.IsOperator():
		return operator
	case tok.IsKeyword():
		return keyword
	}
	return special
}

// TokenKind returns a syntaxhighlight token kind value for the given tok and lit.
func TokenKind(tok token.Token, lit string) syntaxhighlight.Kind {
	switch {
	case tok.IsKeyword() || (tok.IsOperator() && tok <= token.ELLIPSIS):
		return syntaxhighlight.Keyword

	// Literals.
	case tok == token.INT || tok == token.FLOAT || tok == token.IMAG || tok == token.CHAR:
		return syntaxhighlight.Decimal
	case tok == token.STRING:
		return syntaxhighlight.String
	case lit == "true" || lit == "false" || lit == "iota" || lit == "nil":
		return syntaxhighlight.Literal

	case tok == token.COMMENT:
		return syntaxhighlight.Comment
	default:
		return syntaxhighlight.Plaintext
	}
}

// getClass returns the CSS class name associated with tok.
func (h *Highlighter) getClass(tok token.Token) string {
	switch {
	case tok.IsKeyword():
		return h.KeywordClass
	case tok.IsLiteral():
		if tok == token.IDENT {
			return h.IdentClass
		} else {
			return h.LiteralClass
		}
	case tok.IsOperator():
		return h.OperatorClass
	case tok == token.COMMENT:
		return h.CommentClass
	case tok == token.ILLEGAL:
		break
	default:
		panic(fmt.Sprintf("unknown token type: %v", tok))
	}
	return ""
}

func getColor(tok token.Token) string {
	switch {
	case tok.IsKeyword():
		return Colors[Keyword]
	case tok.IsLiteral():
		if tok == token.IDENT {
			return Colors[Identifier]
		} else {
			return Colors[Literal]
		}
	case tok.IsOperator():
		return Colors[Operator]
	case tok == token.COMMENT:
		return Colors[Comment]
	case tok == token.ILLEGAL:
		return Colors[Illegal]
	default:
		panic(fmt.Sprintf("unknown token type: %v", tok))
	}
	return ""
}

func (self *HTMLStyler) Token(tok token.Token) ([]byte, printer.HTMLTag) {
	extra := ""

	if tok.IsKeyword() {
		extra += " go-keyword"
	}

	if tok.IsLiteral() {
		extra += " go-literal"
	}

	if tok.IsOperator() {
		extra += " go-operator"
	}

	self.prev = tok

	return []byte(tok.String()), printer.HTMLTag{
		Start: "<span class=\"go-token" + extra + "\">",
		End:   "</span>",
	}
}