Interpreter

Build on python 😊

• Version Summary:

  • ver0 - Complete (Sample running code in folder)
  • ver1 - Complete (Sample running code in folder)
  • ver2 - Complete (Sample running code in folder)
  • ver3 - Incomplete (Sample code in folder)

• This interpreter is based on Python Object Oriented Programming and uses autolinking of objects to their functions (saying in lame terms). All the __init__ methods and build methods are used to parse the blocks of code sequentially. The eval method in the above interpreter works similar to python eval method and evaluates the parsed tree/structure of the code.

• Basic toy language which is parsed and interpreted using python is as follows:

  n:=2;
  a:=n*2+1;
  while n>0 do
  	while a>0 do
  		print("yo ",a);
  		a:=a-1;
  	done;
  	n:=n-1;
  done;
  if a==0 then
  	print("Machaya");
  else
  	print("Kuch nhi machaya");
  fi;

• Each assignment statement should use := for assignment and contains ; for termination.

• If-Else Statement:

  • Condition in between if and then
  • Statements in between then and fi
  • fi should be followed by a ;

• While Statement:

  • Condition in between while and do
  • Statements in between do and done
  • done should be followed by a ;

• Print Statement:

  • Works same as python print statement and can print multiple arguments at once.

• Println Statement:

  • println statement can be used to print a new line character just like Java

• Good Tutorials 🔖:

  • Almost same toy language but different code structure
  • Brilliantly explained blog