Akshay-Srivatsan / Variableless-Programming

Variableless Programming

Overview:

A programming language which doesn't have any user-definable variables. You have two stacks to store your data and code (a main stack and a data stack). The data stack is local to each "block" of code, while the main stack is global.

Operations:

Note: "the stack" refers to the main stack.

• exit: terminates the program
• { [...] }: defines a block of code, which will be pushed onto the stack without being evaluated
• call: evaluates a block of code on the top of the stack
• return: returns the value at the top of the stack
• return if: evaluates the top value of the stack, and returns the value under it if the top value was the boolean True. Otherwise, discards both values.
• push: pops a value from the main stack and pushes it onto the data stack
• pop: pops a value from the data stack and pushes it onto the main stack
• duplicate: creates a copy of the value at the top of the stack, and pushes the copy onto the top of the stack
• swap: switches the first and second elements on the stack
• less: compares the top two elements on the stack, pushing True if the first is less than the second and pushing False otherwise. The two original elements are discarded.
• greater: compares the top two elements on the stack, pushing True if the first is greater than the second and pushing False otherwise. The two original elements are discarded.
• discard: pops a value from the main stack, but doesn't store it anywhere
• add: adds the top two values on the stack and push the result onto the stack
• negate: replaces the top value on the stack with its additive inverse
• print: writes the top value on the stack to stdout. The value is then discarded.