mafermazu / analyzer-syntactic-for-operator-grammar

Analyzer syntactic for operator grammar

☀️ Analyzer syntactic for operator grammar

Analyzer syntactic for operator grammar in Python.

💻 Requirements

Python3 and pip3.

(opcional) If you want, you can create a virtual environment:

python3 -m venv env

Activate virtual environment:

• Unix/macOS

source env/bin/activate

• Windows

./env\Script\activate

Install requirements:

pip3 install -r requirements.txt

For install coverage

🔥 For run it

python3 main.py

💡 How to use it

1. RULE <no-terminal> [<symbol>]

Define a new rule in the grammar for the symbol. The list of symbols in [<symbol>] is a space-separated (potentially empty) list of terminal symbols or not terminals.

For example:

RULE A a A b - Represents the rule: A → a A b

RULE B - Represents the rule: B → λ

The program should report an error and ignore the action if the symbol placed on the left side of the rule is not non-terminal or if the expressed rule does not correspond to a grammar of operators.

2. INIT <no-terminal>

Sets the initial symbol of the grammar to be the symbol in . For example: INIT B - Sets the symbol B as the initial symbol of the grammar. The program should report an error and ignore the action if the symbol is not non-terminal.

3. PREC <terminal> <op> <terminal>

Establishes the relationship between two terminals (or $). This <op> operation can be:

< when the first terminal has lower precedence than the second

> when the first terminal has higher precedence than the second

= when the first terminal has the same precedence as the second

For example:

PREC + < * - Sets that + has lower precedence than *

PREC (=) - Sets that (has the same precedence as)

PREC $ > n - Sets that $ (border marker) has higher precedence than n

The program should report an error and ignore the action if the symbols involved are not symbols terminals or if the operator in <op> is invalid.

4. BUILD

Build a parser with the information provided so far. Must report calculated values for functions f and g (views in class) or report what to build such functions is impossible, showing evidence for it.

5. PARSE <string>

It performs the parsing process on the string supplied in <string>. Must show each of the steps, including:

Stack - Current status of the stack

Input - Current status of the input. This statement should clearly show the relationships of precedents and the point where it is currently being read (see example).

Action - Action taken (read or reduce by a particular rule)

For example:

PARSE n + n * n - Perform the process on the string n + n * n

The program should report an error and ignore the action if the symbols involved are not symbols terminals, there are non-comparable symbols or if you have not BUILD previously. Between each to symbol terminals in <string> there can be any (potentially zero) amount of Blanks.

6. EXIT

You must exit the simulator.

🔍 For run the tests

coverage3 run --source=analyzer -m unittest test.py

Coverage of the tests

coverage3 report -m

Module	Coverage
Analyzer	65%