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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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// variable represents a GCSS variable. |
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type variable struct { |
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elementBase |
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name string |
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value string |
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} |
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|
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// WriteTo writes the variable to the writer. |
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func (v *variable) WriteTo(w io.Writer) (int64, error) { |
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n, err := w.Write([]byte(v.value)) |
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|
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return int64(n), err |
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} |
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|
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// variableNV extracts a variable name and value |
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// from the line. |
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func variableNV(ln *line) (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 "", "", fmt.Errorf("variable must start with %q [line: %d]", dollarMark, ln.no) |
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} |
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|
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nv := strings.SplitN(s, space, 2) |
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|
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if len(nv) < 2 { |
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return "", "", fmt.Errorf("variable's name and value should be divided by a space [line: %d]", ln.no) |
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} |
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|
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if !strings.HasSuffix(nv[0], colon) { |
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return "", "", fmt.Errorf("variable's name should end with a colon [line: %d]", ln.no) |
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} |
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|
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return strings.TrimSuffix(strings.TrimPrefix(nv[0], dollarMark), colon), nv[1], nil |
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} |
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|
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// newVariable creates and returns a variable. |
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func newVariable(ln *line, parent element) (*variable, error) { |
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name, value, err := variableNV(ln) |
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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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if strings.HasSuffix(value, semicolon) { |
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return nil, fmt.Errorf("variable must not end with %q", semicolon) |
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} |
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|
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return &variable{ |
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elementBase: newElementBase(ln, parent), |
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name: name, |
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value: value, |
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}, nil |
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} |
