Tea Programming Language

Implementation a programming language named Tea. Exercise related to this topics:

• Recursive Programming
• C++ (as language)
• 2 Dimensional Arrays
• Struct Templates
• Stack Implementation
• Data Structures

Problem

A company's engineers decided to write simple programming language. That language would be easy to write, so has simple rules. Tea programs consist of subsequent lines of statements. Each statement has a simple job. There are 7 statements and 5 variables.

Statements

inc

Increments arg1 by arg2

dec

Decrements arg2 by arg2

mul

Multiplies arg1 by arg2

div

Divides arg1 by arg2

function

Defines a function named arg1

call

Calls arg1 with argument arg2

return

returns arg1

Variables

Engineers of the company all hated local variable declerations. So, Tea does not allow define variables. There are 5 predefined variables: [a,b,c,d,e]. A function can use these variables by accessing and operating on them. They all specific to a function. Every function uses different [a,b,c,d,e] variables. They are all 0 at initialization.

Functions

Functions are defined like;

  function foo
  //operations with call, mul, inc, div, dec
  return a  // or any variable 

Functions are called like;

call foo e

This function call initializes all variables for this call except e. e is taken by parent functions variable. (But it initializes again for new function, changes on it does not change parent's e). Due to return a statement, function finally assigns its a to the parent's a variable. Each Tea program has a main function and starts from this function. It is not necessity to place functions in certain order. A function can be defined and called before or after another functions including main.

Input / Coding with tea

example1.tea

  function main
  inc a 2
  inc b 3
  call foo a
  call bar b
  inc d a
  inc d c
  return d
  function foo
  inc a 4
  div a 2
  return a
  function bar
  inc c 7
  dec c b
  return c

workflow of example1.tea

Lines are 0-indexed

Executed Line	Next Line	[a,b,c,d,e]
0	1	0,0,0,0,0
1	2	2,0,0,0,0
2	3	2,3,0,0,0
3	9	2,0,0,0,0
9	10	6,0,0,0,0
10	11	3,0,0,0,0
11	4	3,3,0,0,0
4	13	0,3,0,0,0
13	14	0,3,7,0,0
14	15	0,3,4,0,0
15	5	3,3,4,0,0
5	6	3,3,4,3,0
6	7	3,3,4,7,0
7		3,3,4,7,0

Then program outputs 7.

How to Run

compile:

g++ tea.cpp -o tea.exe

run:

tea.exe example_code

Notes

As I code this program, there is a problem with variables. They should initialize at start but every function uses new set of variables. Also functions can call functions, so i cannot use just one set of inputs for main, one for called functions. I needed segmentated memory. But I had limitation which is set by my instructor. In this limits:

I implemented variables as 2D array: T variables[LANGUAGE_DEPTH][5]; . Which means I have LANGUAGE_DEPTH times array of 5 variables. Variables[0] is set of variables of main function. If main calls a function i use Variables[1] for it. If it calls another, program uses Variables[2]. I say this k number in Variables[k] depth or degree of function. I use LANGUAGE_DEPTH property to scale power of Tea programming language. In other words, capability to work with nested functions. You can have more powerfull tea engine with increasing it. (Default: 5).