plates

plates is an esoteric, imperative, stack-based programming language.

Instructions

• PUSH <value>: pushes a word onto the stack.
  • If an unsigned 32-bit integer is provided, that value is pushed onto the stack.
  • If a function name is provided, that function is pushed onto the stack.
  • If the token * is provided, a random byte (from a uniform distribution) is generated.
• DEFN <function-name> (<arg-count>) { <instructions> }: defines a function. When this function is called, the top arg-count values on the stack will be popped. They can then be accessed as $0 (for the value that was on top of the stack), $1, $2, and so on. Note that nested function calls will overwrite arguments.
• CALLIF: pops the two values at the top of the stack. The top-most value must be a function and the one below that must be a data word. If the data word is nonzero, the function is executed.
• EXIT: terminates the program.

Functions

Functions can be pushed onto the stack and then called. When called, they can modify the state of the stack.

Built-in functions

• __print__: displays the data words starting at the top of the stack and continuing downwards until it reaches a zero word. Each word is interpreted as a UTF-32 character. The printed data will be popped from the stack.
• __input__: reads one line of input from stdin and places each character onto the stack (with the first character read on top). The characters are represented in UTF-32.
• __birl__: performs bitwise material implication (x => y) on the data words at the top of the stack, then rotates the result left by one bit. In other words, if a is the value at the top of the stack and b is the value below that, this function replaces them with (!a | b).rotate_left(1).

Comments

When // is encountered, everything until the end of that line is treated as a comment.