Interpreter for Simple Language

This program demonstrates how to make an interpreter for a programming language. It uses the "Gang of Four" Intepreter design pattern to implement a simple, Pascal-like language. It is written in C++ and compiles under Windows, Linux and MacOS.

To build it

• Install Qt before building
• Make

cd Src
qmake Interpreter.pro
make

Usage

interpreter <action> <filename>

Where action is /p to pretty-print or /e to execute

Example

The grammar of the language is Pascal-like. Here is a sample program that prints the first 100 prime numbers.

This example is available in the "Samples" directory. You can run it by typing interpreter /e ../samples/compute_primes.txt (use backslashes for Windows)

primecount := 0
testprime := 1

while primecount < 100
begin

	isprime := 1

	factor := 2
	while isprime and factor * factor < testprime + 1
	begin
		isprime := testprime mod factor <> 0
		factor := factor + 1
	end

	if isprime = 1
	begin
		print testprime
		primecount := primecount + 1

	end	

	testprime := testprime + 1

end

Author

• @jamesdhutton (github)

Qt Project

• Project is port for Qt project. (by j2doll)