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package gcss |
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|
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import ( |
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"fmt" |
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"io" |
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"strings" |
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) |
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|
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// mixinDeclaration represents a mixin declaration. |
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type mixinDeclaration struct { |
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elementBase |
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name string |
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paramNames []string |
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} |
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|
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// WriteTo writes the selector to the writer. |
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func (md *mixinDeclaration) WriteTo(w io.Writer) (int64, error) { |
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return 0, nil |
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} |
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|
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// mixinNP extracts a mixin name and parameters from the line. |
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func mixinNP(ln *line, isDeclaration bool) (string, []string, error) { |
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s := strings.TrimSpace(ln.s) |
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|
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if !strings.HasPrefix(s, dollarMark) { |
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return "", nil, fmt.Errorf("mixin must start with %q [line: %d]", dollarMark, ln.no) |
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} |
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|
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s = strings.TrimPrefix(s, dollarMark) |
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|
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np := strings.Split(s, openParenthesis) |
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|
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if len(np) != 2 { |
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return "", nil, fmt.Errorf("mixin's format is invalid [line: %d]", ln.no) |
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} |
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|
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paramsS := strings.TrimSpace(np[1]) |
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|
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if !strings.HasSuffix(paramsS, closeParenthesis) { |
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return "", nil, fmt.Errorf("mixin must end with %q [line: %d]", closeParenthesis, ln.no) |
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} |
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|
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paramsS = strings.TrimSuffix(paramsS, closeParenthesis) |
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|
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if strings.Index(paramsS, closeParenthesis) != -1 { |
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return "", nil, fmt.Errorf("mixin's format is invalid [line: %d]", ln.no) |
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} |
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|
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var params []string |
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|
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if paramsS != "" { |
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params = strings.Split(paramsS, comma) |
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} |
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|
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for i, p := range params { |
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p = strings.TrimSpace(p) |
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|
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if isDeclaration { |
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if !strings.HasPrefix(p, dollarMark) { |
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return "", nil, fmt.Errorf("mixin's parameter must start with %q [line: %d]", dollarMark, ln.no) |
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} |
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|
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p = strings.TrimPrefix(p, dollarMark) |
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} |
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|
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params[i] = p |
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} |
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|
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return np[0], params, nil |
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} |
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|
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// newMixinDeclaration creates and returns a mixin declaration. |
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func newMixinDeclaration(ln *line, parent element) (*mixinDeclaration, error) { |
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name, paramNames, err := mixinNP(ln, true) |
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|
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if err != nil { |
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return nil, err |
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} |
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|
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return &mixinDeclaration{ |
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elementBase: newElementBase(ln, parent), |
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name: name, |
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paramNames: paramNames, |
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}, nil |
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} |
