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package gcss |
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|
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import "strings" |
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|
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// Special characters |
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const ( |
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cr = "\r" |
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lf = "\n" |
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crlf = "\r\n" |
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space = " " |
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colon = ":" |
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comma = "," |
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openBrace = "{" |
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closeBrace = "}" |
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semicolon = ";" |
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ampersand = "&" |
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atMark = "@" |
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dollarMark = "$" |
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openParenthesis = "(" |
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closeParenthesis = ")" |
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slash = "/" |
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doubleSlash = slash + slash |
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) |
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|
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// parse parses the string, generates the elements |
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// and returns the two channels: the first one returns |
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// the generated elements and the last one returns |
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// an error when it occurs. |
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func parse(lines []string) (<-chan element, <-chan error) { |
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elemc := make(chan element, len(lines)) |
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errc := make(chan error) |
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|
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go func() { |
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i := 0 |
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l := len(lines) |
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|
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for i < l { |
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// Fetch a line. |
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ln := newLine(i+1, lines[i]) |
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i++ |
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|
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// Ignore the empty line. |
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if ln.isEmpty() { |
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continue |
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} |
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|
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if ln.isTopIndent() { |
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elem, err := newElement(ln, nil) |
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|
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if err != nil { |
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errc <- err |
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return |
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} |
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|
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if err := appendChildren(elem, lines, &i, l); err != nil { |
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errc <- err |
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return |
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} |
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|
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elemc <- elem |
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} |
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} |
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|
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close(elemc) |
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}() |
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|
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return elemc, errc |
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} |
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|
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// appendChildren parses the lines and appends the child elements |
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// to the parent element. |
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func appendChildren(parent element, lines []string, i *int, l int) error { |
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for *i < l { |
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// Fetch a line. |
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ln := newLine(*i+1, lines[*i]) |
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|
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// Ignore the empty line. |
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if ln.isEmpty() { |
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*i++ |
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return nil |
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} |
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|
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ok, err := ln.childOf(parent) |
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|
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if err != nil { |
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return err |
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} |
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|
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if !ok { |
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return nil |
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} |
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|
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child, err := newElement(ln, parent) |
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|
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if err != nil { |
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return err |
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} |
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|
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parent.AppendChild(child) |
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|
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*i++ |
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|
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if err := appendChildren(child, lines, i, l); err != nil { |
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return err |
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} |
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} |
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|
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return nil |
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} |
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|
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// formatLF replaces the line feed codes with LF and |
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// returns the result string. |
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func formatLF(s string) string { |
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return strings.Replace(strings.Replace(s, crlf, lf, -1), cr, lf, -1) |
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} |