29 lines
1.2 KiB
Markdown
29 lines
1.2 KiB
Markdown
# Well-parenthesized language parser
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This project is a JavaCC parser configuration which generates a parser for a language with well-balanced parentheses.
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The features that this language has is:
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- Each string accepted by the language consists of multiple lines (but at least 1 line).
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- Lines must not be empty.
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- Lines must contain well-balanced parentheses, e.g. `()`, `()()()`, `(()())`, `(((())))`.
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- Only parentheses are allowed, so any other character makes the input invalid.
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- (As an exception to the first rule) there must be a blank final line at the end of the input.
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E.g. the following is a good input to the parser:
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```
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()(())
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(())(((()())))
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((((((((((()))))))))))
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(())()()()()()
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((()()())()()(()(())))()
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<blank line here>
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```
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## How to run
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To build the Java code and run:
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`./run.sh`. This is an alias for:
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```bash
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javacc assignment.jj && javac *.java && java Assignment < test.txt > output.txt 2> err.txt
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```
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### Output
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The standard output stream will contain the parser's decision as to whether the string is valid — the output will either be `PASS` or `FAIL`.
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If it is `FAIL`, the standard error will also contain the line number of the first error that caused the invalidity. |