#!/usr/bin/env python # -*- coding: utf-8 -*- # # Copyright © 2022 Simon Forman # # This file is part of Thun # # Thun is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # Thun is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with Thun. If not see . # ''' ████████╗██╗ ██╗██╗ ██╗███╗ ██╗ ╚══██╔══╝██║ ██║██║ ██║████╗ ██║ ██║ ███████║██║ ██║██╔██╗ ██║ ██║ ██╔══██║██║ ██║██║╚██╗██║ ██║ ██║ ██║╚██████╔╝██║ ╚████║ ╚═╝ ╚═╝ ╚═╝ ╚═════╝ ╚═╝ ╚═══╝ This script implements an interpreter for a dialect of Joy. ''' from functools import wraps from inspect import getdoc from re import Scanner from traceback import print_exc import operator class NotAListError(Exception): ''' Raised when a stack is expected but not received. ''' class NotAnIntError(Exception): pass class NotABoolError(Exception): pass class ParseError(ValueError): ''' Raised when there is a error while parsing text. ''' class StackUnderflowError(Exception): pass class UnknownSymbolError(KeyError): pass def isnt_int(i): ''' Raise NotAnIntError if i isn't an integer. (Booleans are not integers in Joy.) ''' if not isinstance(i, int) or isinstance(i, bool): raise NotAnIntError(f'Not an integer: {_s(i)}') def isnt_bool(b): ''' Raise NotABoolError if b isn't a Boolean. ''' if not isinstance(b, bool): raise NotABoolError(f'Not a Boolean value: {_s(b)}') def isnt_stack(el): ''' Raise NotAListError if el isn't a stack/quote/list. ''' if not isinstance(el, tuple): raise NotAListError(f'Not a list: {_s(el)}') ''' ██╗███╗ ██╗████████╗███████╗██████╗ ██████╗ ██████╗ ███████╗████████╗███████╗██████╗ ██║████╗ ██║╚══██╔══╝██╔════╝██╔══██╗██╔══██╗██╔══██╗██╔════╝╚══██╔══╝██╔════╝██╔══██╗ ██║██╔██╗ ██║ ██║ █████╗ ██████╔╝██████╔╝██████╔╝█████╗ ██║ █████╗ ██████╔╝ ██║██║╚██╗██║ ██║ ██╔══╝ ██╔══██╗██╔═══╝ ██╔══██╗██╔══╝ ██║ ██╔══╝ ██╔══██╗ ██║██║ ╚████║ ██║ ███████╗██║ ██║██║ ██║ ██║███████╗ ██║ ███████╗██║ ██║ ╚═╝╚═╝ ╚═══╝ ╚═╝ ╚══════╝╚═╝ ╚═╝╚═╝ ╚═╝ ╚═╝╚══════╝ ╚═╝ ╚══════╝╚═╝ ╚═╝ ''' def joy(stack, expr, dictionary): ''' Evaluate a Joy expression on a stack. This function iterates through a sequence of terms. Literals are put onto the stack and Symbols are looked up in the dictionary and the functions they denote are executed. :param stack stack: The stack. :param stack expression: The expression to evaluate. :param dict dictionary: A ``dict`` mapping names to Joy functions. :rtype: (stack, (), dictionary) ''' while expr: term, expr = expr if isinstance(term, Symbol): try: func = dictionary[term] except KeyError: raise UnknownSymbolError(term) from None stack, expr, dictionary = func(stack, expr, dictionary) else: stack = term, stack return stack, expr, dictionary ''' ██████╗ █████╗ ██████╗ ███████╗███████╗██████╗ ██╔══██╗██╔══██╗██╔══██╗██╔════╝██╔════╝██╔══██╗ ██████╔╝███████║██████╔╝███████╗█████╗ ██████╔╝ ██╔═══╝ ██╔══██║██╔══██╗╚════██║██╔══╝ ██╔══██╗ ██║ ██║ ██║██║ ██║███████║███████╗██║ ██║ ╚═╝ ╚═╝ ╚═╝╚═╝ ╚═╝╚══════╝╚══════╝╚═╝ ╚═╝ There is a single function for converting text to joy expressions as well as a Symbol class and an Exception type. The Symbol string class is used by the interpreter to recognize literals by the fact that they are not Symbol objects. A crude grammar:: joy := * term := | 'true' | 'false' | '[' ']' | A Joy expression is a sequence of zero or more terms. A term is a literal value (integer, Boolean, or quoted Joy expression) or a function symbol. Function symbols are sequences of non-blanks and cannot contain square brackets. Terms must be separated by blanks, which can be omitted around square brackets. ''' JOY_BOOL_LITERALS = _F, _T = 'false', 'true' BRACKETS = r'\[|\]' # Left or right square bracket. BLANKS = r'\s+' # One-or-more blankspace. WORDS = ( '[' # Character class '^' # not a '[' # left square bracket nor a r'\]' # right square bracket (escaped so it doesn't close the character class) r'\s' # nor blankspace ']+' # end character class, one-or-more. ) token_scanner = Scanner( [ (BRACKETS, lambda _, token: token), (BLANKS, None), (WORDS, lambda _, token: token), ] ) class Symbol(str): ''' A string class that represents Joy function names. ''' __repr__ = str.__str__ def text_to_expression(text): ''' Convert a string to a Joy expression. When supplied with a string this function returns a Python datastructure that represents the Joy datastructure described by the text expression. Any unbalanced square brackets will raise a ParseError. :param str text: Text to convert. :rtype: stack :raises ParseError: if the parse fails. ''' return _parse(_tokenize(text)) def _tokenize(text): '''Convert a text into a stream of tokens. Converts function names to Symbols. Raise ParseError (with some of the failing text) if the scan fails. ''' tokens, rest = token_scanner.scan(text) if rest: raise ParseError( 'Scan failed at position %i, %r' % (len(text) - len(rest), rest[:10]) ) return tokens def _parse(tokens): ''' Return a stack/list expression of the tokens. ''' frame = [] stack = [] for tok in tokens: if tok == '[': stack.append(frame) frame = [] elif tok == ']': v = frame try: frame = stack.pop() except IndexError: raise ParseError('Extra closing bracket.') from None frame.append(list_to_stack(v)) elif tok == _T: frame.append(True) elif tok == _F: frame.append(False) else: try: thing = int(tok) except ValueError: thing = Symbol(tok) frame.append(thing) if stack: raise ParseError('Unclosed bracket.') return list_to_stack(frame) r''' ███████╗████████╗ █████╗ ██████╗██╗ ██╗ ██╔════╝╚══██╔══╝██╔══██╗██╔════╝██║ ██╔╝ ███████╗ ██║ ███████║██║ █████╔╝ ╚════██║ ██║ ██╔══██║██║ ██╔═██╗ ███████║ ██║ ██║ ██║╚██████╗██║ ██╗ ╚══════╝ ╚═╝ ╚═╝ ╚═╝ ╚═════╝╚═╝ ╚═╝ When talking about Joy we use the terms "stack", "quote", "sequence", "list", and others to mean the same thing: a simple linear datatype that permits certain operations such as iterating and pushing and popping values from (at least) one end. In describing Joy I have used the term quotation to describe all of the above, because I needed a word to describe the arguments to combinators which fulfill the same role in Joy as lambda abstractions (with variables) fulfill in the more familiar functional languages. I use the term list for those quotations whose members are what I call literals: numbers, characters, truth values, sets, strings and other quotations. All these I call literals because their occurrence in code results in them being pushed onto the stack. But I also call [London Paris] a list. So, [dup \*] is a quotation but not a list. `"A Conversation with Manfred von Thun" w/ Stevan Apter `_ There is no "Stack" Python class, instead we use the `cons list`_, a venerable two-tuple recursive sequence datastructure, where the empty tuple ``()`` is the empty stack and ``(head, rest)`` gives the recursive form of a stack with one or more items on it:: stack := () | (item, stack) Putting some numbers onto a stack:: () (1, ()) (2, (1, ())) (3, (2, (1, ()))) ... Python has very nice "tuple packing and unpacking" in its syntax which means we can directly "unpack" the expected arguments to a Joy function. We assign the argument stack to the expected structure of the stack and Python takes care of unpacking the incoming tuple and assigning values to the names. (Note that Python syntax doesn't require parentheses around tuples used in expressions where they would be redundant.) def dup(stack): head, tail = stack return head, (head, tail) We have two very simple functions, one to build up a stack from a Python list and another to iterate through a stack and yield its items one-by-one in order. There are also two functions to generate string representations of stacks. They only differ in that one prints the terms in stack from left-to-right while the other prints from right-to-left. In both functions *internal stacks* are printed left-to-right. These functions are written to support :doc:`../pretty`. .. _cons list: https://en.wikipedia.org/wiki/Cons#Lists ''' def list_to_stack(el, stack=()): ''' Convert a Python list (or other sequence) to a Joy stack:: [1, 2, 3] -> (1, (2, (3, ()))) :param list el: A Python list or other sequence (iterators and generators won't work because ``reverse()`` is called on ``el``.) :param stack stack: A stack, optional, defaults to the empty stack. This allows for concatinating Python lists (or other sequence objects) onto an existing Joy stack. :rtype: stack ''' for item in reversed(el): stack = item, stack return stack def iter_stack(stack): ''' Iterate through the items on the stack. :param stack stack: A stack. :rtype: iterator ''' while stack: item, stack = stack yield item def concat(quote, expression): ''' Concatinate quote onto expression. In joy [1 2] [3 4] would become [1 2 3 4]. :param stack quote: A stack. :param stack expression: A stack. :rtype: stack ''' # This (below) is the fastest implementation, but will trigger # RuntimeError: maximum recursion depth exceeded # on quotes longer than sys.getrecursionlimit(). # :raises RuntimeError: if quote is larger than sys.getrecursionlimit(). ## return (quote[0], concat(quote[1], expression)) if quote else expression # Original implementation. ## return list_to_stack(list(iter_stack(quote)), expression) # In-lining is slightly faster (and won't break the # recursion limit on long quotes.) isnt_stack(quote) isnt_stack(expression) temp = [] while quote: item, quote = quote temp.append(item) for item in reversed(temp): expression = item, expression return expression def get_n_items(n, stack): ''' Return items and remainder of stack. Raise StackUnderflowError if there are fewer than n items on the stack. ''' assert n > 0, repr(n) temp = [] while n > 0: n -= 1 try: item, stack = stack except ValueError: raise StackUnderflowError( 'Not enough values on stack.' ) from None temp.append(item) temp.append(stack) return tuple(temp) def reversed_stack(stack): ''' Return list_reverseiterator object for a stack. ''' return reversed(list(iter_stack(stack))) ''' ██████╗ ██████╗ ██╗███╗ ██╗████████╗███████╗██████╗ ██╔══██╗██╔══██╗██║████╗ ██║╚══██╔══╝██╔════╝██╔══██╗ ██████╔╝██████╔╝██║██╔██╗ ██║ ██║ █████╗ ██████╔╝ ██╔═══╝ ██╔══██╗██║██║╚██╗██║ ██║ ██╔══╝ ██╔══██╗ ██║ ██║ ██║██║██║ ╚████║ ██║ ███████╗██║ ██║ ╚═╝ ╚═╝ ╚═╝╚═╝╚═╝ ╚═══╝ ╚═╝ ╚══════╝╚═╝ ╚═╝ ''' def stack_to_string(stack): ''' Return a "pretty print" string for a stack. The items are written right-to-left:: (top, (second, ...)) -> '... second top' :param stack stack: A stack. :rtype: str ''' return _to_string(stack, reversed_stack) def expression_to_string(expression): ''' Return a "pretty print" string for a expression. The items are written left-to-right:: (top, (second, ...)) -> 'top second ...' :param stack expression: A stack. :rtype: str ''' return _to_string(expression, iter_stack) def _joy_repr(thing): return ( JOY_BOOL_LITERALS[thing] if isinstance(thing, bool) else repr(thing) ) def _to_string(stack, f): if not isinstance(stack, tuple): return _joy_repr(stack) if not stack: return '' # shortcut return ' '.join(map(_s, f(stack))) def _s(s): return ( '[%s]' % expression_to_string(s) if isinstance(s, tuple) else _joy_repr(s) ) ''' ██████╗ ███████╗██████╗ ██╗ ██╔══██╗██╔════╝██╔══██╗██║ ██████╔╝█████╗ ██████╔╝██║ ██╔══██╗██╔══╝ ██╔═══╝ ██║ ██║ ██║███████╗██║ ███████╗ ╚═╝ ╚═╝╚══════╝╚═╝ ╚══════╝ Read-Evaluate-Print Loop ''' def repl(stack=(), dictionary=None): ''' Read-Evaluate-Print Loop Accept input and run it on the stack, loop. :param stack stack: The stack. :param dict dictionary: A ``dict`` mapping names to Joy functions. :rtype: stack ''' if dictionary is None: dictionary = {} try: while True: print() print(stack_to_string(stack), '<-top') print() try: text = input('joy? ') except (EOFError, KeyboardInterrupt): break try: stack, _, dictionary = run(text, stack, dictionary) except SystemExit as e: raise SystemExit from e except: print_exc() except SystemExit as e: raise SystemExit from e except: print_exc() print() return stack def run(text, stack, dictionary): ''' Return the stack resulting from running the Joy code text on the stack. :param str text: Joy code. :param stack stack: The stack. :param dict dictionary: A ``dict`` mapping names to Joy functions. :rtype: (stack, (), dictionary) ''' expr = text_to_expression(text) return joy(stack, expr, dictionary) def interp(stack=(), dictionary=None): ''' Simple REPL with no extra output, suitable for use in scripts. ''' if dictionary is None: dictionary = {} try: while True: try: text = input() except (EOFError, KeyboardInterrupt): break try: stack, _, dictionary = run(text, stack, dictionary) except UnknownSymbolError as sym: print('Unknown:', sym) except StackUnderflowError as e: print(e) # 'Not enough values on stack.' except NotAnIntError as e: print(e) except NotAListError as e: print(e) except SystemExit as e: raise SystemExit from e except: print_exc() print(stack_to_string(stack)) except SystemExit as e: raise SystemExit from e except: print_exc() return stack ''' ██████╗ ██╗ ██████╗████████╗██╗ ██████╗ ███╗ ██╗ █████╗ ██████╗ ██╗ ██╗ ██╔══██╗██║██╔════╝╚══██╔══╝██║██╔═══██╗████╗ ██║██╔══██╗██╔══██╗╚██╗ ██╔╝ ██║ ██║██║██║ ██║ ██║██║ ██║██╔██╗ ██║███████║██████╔╝ ╚████╔╝ ██║ ██║██║██║ ██║ ██║██║ ██║██║╚██╗██║██╔══██║██╔══██╗ ╚██╔╝ ██████╔╝██║╚██████╗ ██║ ██║╚██████╔╝██║ ╚████║██║ ██║██║ ██║ ██║ ╚═════╝ ╚═╝ ╚═════╝ ╚═╝ ╚═╝ ╚═════╝ ╚═╝ ╚═══╝╚═╝ ╚═╝╚═╝ ╚═╝ ╚═╝ ''' # This is the main dict we're building. _dictionary = {} def inscribe(function, d=_dictionary): ''' A decorator to inscribe functions into the default dictionary. ''' d[function.__name__.rstrip('_')] = function return function def initialize(): ''' Return a dictionary of Joy functions for use with joy(). ''' return _dictionary.copy() def SimpleFunctionWrapper(f): ''' Wrap functions that take and return just a stack. ''' @wraps(f) def SimpleFunctionWrapper_inner(stack, expr, dictionary): return f(stack), expr, dictionary return SimpleFunctionWrapper_inner @inscribe def words(stack, expression, dictionary): ''' Put a list of all the words in alphabetical order onto the stack. ''' w = () for name in reversed(sorted(dictionary)): if name.startswith('_'): continue w = (Symbol(name), ()), w return (w, stack), expression, dictionary HELP_TEMPLATE = '''\ ==== Help on %s ==== %s ---- end ( %s ) ''' @inscribe def help_(stack, expression, dictionary): ''' Accepts a quoted symbol on the top of the stack and prints its docs. ''' ((symbol, _), stack) = stack word = dictionary[symbol] print(HELP_TEMPLATE % (symbol, getdoc(word), symbol)) return stack, expression, dictionary ''' ██████╗ ██████╗ ███╗ ███╗██████╗ ██╗███╗ ██╗ █████╗ ████████╗ ██████╗ ██████╗ ███████╗ ██╔════╝██╔═══██╗████╗ ████║██╔══██╗██║████╗ ██║██╔══██╗╚══██╔══╝██╔═══██╗██╔══██╗██╔════╝ ██║ ██║ ██║██╔████╔██║██████╔╝██║██╔██╗ ██║███████║ ██║ ██║ ██║██████╔╝███████╗ ██║ ██║ ██║██║╚██╔╝██║██╔══██╗██║██║╚██╗██║██╔══██║ ██║ ██║ ██║██╔══██╗╚════██║ ╚██████╗╚██████╔╝██║ ╚═╝ ██║██████╔╝██║██║ ╚████║██║ ██║ ██║ ╚██████╔╝██║ ██║███████║ ╚═════╝ ╚═════╝ ╚═╝ ╚═╝╚═════╝ ╚═╝╚═╝ ╚═══╝╚═╝ ╚═╝ ╚═╝ ╚═════╝ ╚═╝ ╚═╝╚══════╝ ''' @inscribe def branch(stack, expr, dictionary): ''' Use a Boolean value to select one of two quoted programs to run. :: branch == roll< choice i :: False [F] [T] branch -------------------------- F True [F] [T] branch ------------------------- T ''' then, else_, flag, stack = get_n_items(3, stack) isnt_bool(flag) isnt_stack(else_) isnt_stack(then) do = then if flag else else_ return stack, concat(do, expr), dictionary @inscribe def dip(stack, expr, dictionary): ''' The dip combinator expects a quoted program on the stack and below it some item, it hoists the item into the expression and runs the program on the rest of the stack. :: ... x [Q] dip ------------------- ... Q x ''' quote, x, stack = get_n_items(2, stack) return stack, concat(quote, (x, expr)), dictionary @inscribe def i(stack, expr, dictionary): ''' The i combinator expects a quoted program on the stack and unpacks it onto the pending expression for evaluation. :: [Q] i ----------- Q ''' quote, stack = get_n_items(1, stack) return stack, concat(quote, expr), dictionary LOOP = Symbol('loop') @inscribe def loop(stack, expr, dictionary): ''' Basic loop combinator. :: ... True [Q] loop ----------------------- ... Q [Q] loop ... False [Q] loop ------------------------ ... ''' quote, flag, stack = get_n_items(2, stack) isnt_bool(flag) isnt_stack(quote) if flag: expr = concat(quote, (quote, (LOOP, expr))) return stack, expr, dictionary @inscribe def halt(stack, expr, dictionary): ''' Put the pending expression onto the stack and halt. ''' return (expr, stack), (), dictionary @inscribe def quit(stack, expr, dictionary): ''' Stop the interpreter. ''' raise SystemExit ''' ██████╗ ██████╗ ██████╗ ███████╗ ██╗ ██╗ ██████╗ ██████╗ ██████╗ ███████╗ ██╔════╝██╔═══██╗██╔══██╗██╔════╝ ██║ ██║██╔═══██╗██╔══██╗██╔══██╗██╔════╝ ██║ ██║ ██║██████╔╝█████╗ ██║ █╗ ██║██║ ██║██████╔╝██║ ██║███████╗ ██║ ██║ ██║██╔══██╗██╔══╝ ██║███╗██║██║ ██║██╔══██╗██║ ██║╚════██║ ╚██████╗╚██████╔╝██║ ██║███████╗ ╚███╔███╔╝╚██████╔╝██║ ██║██████╔╝███████║ ╚═════╝ ╚═════╝ ╚═╝ ╚═╝╚══════╝ ╚══╝╚══╝ ╚═════╝ ╚═╝ ╚═╝╚═════╝ ╚══════╝ ''' @inscribe @SimpleFunctionWrapper def clear(stack): ''' Clear everything from the stack. :: clear == stack [pop stack] loop ... clear --------------- ''' return () @inscribe @SimpleFunctionWrapper def concat_(stack): ''' Concatinate the two lists on the top of the stack. :: [a b c] [d e f] concat ---------------------------- [a b c d e f] ''' tos, second, stack = get_n_items(2, stack) return concat(second, tos), stack @inscribe @SimpleFunctionWrapper def cons(stack): ''' Given an item and a list, append the item to the list to make a new list. :: a [...] cons ------------------ [a ...] Cons is a venerable old function from Lisp ( https://en.wikipedia.org/wiki/Cons#Lists ). Its inverse operation is uncons. ''' s0, a1, stack = get_n_items(2, stack) isnt_stack(s0) return ((a1, s0), stack) @inscribe @SimpleFunctionWrapper def dup(stack): ''' "Dup"licate the top item on the stack. :: a dup ----------- a a ''' a1, stack = get_n_items(1, stack) return a1, (a1, stack) @inscribe @SimpleFunctionWrapper def first(stack): ''' Replace a list with its first item. [a ...] -------------- a ''' s0, stack = get_n_items(1, stack) isnt_stack(s0) a1, _ = get_n_items(1, s0) return a1, stack @inscribe @SimpleFunctionWrapper def pop(stack): ''' Pop the top item from the stack and discard it. a pop ----------- ''' try: _, stack = stack except ValueError: raise StackUnderflowError('Cannot pop empty stack.') from None return stack @inscribe @SimpleFunctionWrapper def rest(stack): ''' Replace a list with its tail. [a b c] rest ------------------ [b c] ''' s0, stack = get_n_items(1, stack) isnt_stack(s0) try: _, s1 = s0 except ValueError: raise StackUnderflowError( 'Cannot take rest of empty list.' ) from None return s1, stack @inscribe @SimpleFunctionWrapper def stack(stack): ''' Put the stack onto the stack. ... c b a stack --------------------------- ... c b a [a b c ...] ''' return stack, stack @inscribe @SimpleFunctionWrapper def swaack(stack): ''' Swap stack. Take a list from the top of the stack, replace the stack with the list, and put the old stack onto it. 1 2 3 [4 5 6] swaack -------------------------- 6 5 4 [3 2 1] ''' s1, s0 = get_n_items(1, stack) isnt_stack(s1) return s0, s1 @inscribe @SimpleFunctionWrapper def swap(stack): ''' Swap the top two items on the stack. a b swap -------------- b a ''' a2, a1, stack = get_n_items(2, stack) return (a1, (a2, stack)) def BinaryLogicWrapper(f): ''' Wrap functions that take two numbers and return a single result. ''' @wraps(f) def BinaryLogicWrapper_inner(stack, expression, dictionary): a, b, stack = get_n_items(2, stack) isnt_bool(a) isnt_bool(b) result = f(b, a) return (result, stack), expression, dictionary return BinaryLogicWrapper_inner def BinaryMathWrapper(func): ''' Wrap functions that take two numbers and return a single result. ''' @wraps(func) def BinaryMathWrapper_inner(stack, expression, dictionary): a, b, stack = get_n_items(2, stack) isnt_int(a) isnt_int(b) result = func(b, a) return (result, stack), expression, dictionary return BinaryMathWrapper_inner def UnaryLogicWrapper(f): ''' Wrap functions that take one argument and return a single result. ''' @wraps(f) def UnaryLogicWrapper_inner(stack, expression, dictionary): a, stack = get_n_items(1, stack) isnt_bool(a) result = f(a) return (result, stack), expression, dictionary return UnaryLogicWrapper_inner def UnaryMathWrapper(f): ''' Wrap functions that take one argument and return a single result. ''' @wraps(f) def UnaryMathWrapper_inner(stack, expression, dictionary): a, stack = get_n_items(1, stack) isnt_int(a) result = f(a) return (result, stack), expression, dictionary return UnaryMathWrapper_inner def UnaryWrapper(f): ''' Wrap functions that take one argument and return a single result. ''' @wraps(f) def UnaryWrapper_inner(stack, expression, dictionary): a, stack = get_n_items(1, stack) result = f(a) return (result, stack), expression, dictionary return UnaryWrapper_inner for F in ( ## ██████╗ ██████╗ ███╗ ███╗██████╗ █████╗ ██████╗ ██╗███████╗██╗ ██████╗ ███╗ ██╗ ##██╔════╝██╔═══██╗████╗ ████║██╔══██╗██╔══██╗██╔══██╗██║██╔════╝██║██╔═══██╗████╗ ██║ ##██║ ██║ ██║██╔████╔██║██████╔╝███████║██████╔╝██║███████╗██║██║ ██║██╔██╗ ██║ ##██║ ██║ ██║██║╚██╔╝██║██╔═══╝ ██╔══██║██╔══██╗██║╚════██║██║██║ ██║██║╚██╗██║ ##╚██████╗╚██████╔╝██║ ╚═╝ ██║██║ ██║ ██║██║ ██║██║███████║██║╚██████╔╝██║ ╚████║ ## ╚═════╝ ╚═════╝ ╚═╝ ╚═╝╚═╝ ╚═╝ ╚═╝╚═╝ ╚═╝╚═╝╚══════╝╚═╝ ╚═════╝ ╚═╝ ╚═══╝ BinaryMathWrapper(operator.eq), BinaryMathWrapper(operator.ge), BinaryMathWrapper(operator.gt), BinaryMathWrapper(operator.le), BinaryMathWrapper(operator.lt), BinaryMathWrapper(operator.ne), ##██╗ ██████╗ ██████╗ ██╗ ██████╗ ##██║ ██╔═══██╗██╔════╝ ██║██╔════╝ ##██║ ██║ ██║██║ ███╗██║██║ ##██║ ██║ ██║██║ ██║██║██║ ##███████╗╚██████╔╝╚██████╔╝██║╚██████╗ ##╚══════╝ ╚═════╝ ╚═════╝ ╚═╝ ╚═════╝ UnaryWrapper(bool), # Convert any value to Boolean. # (The only polymorphic function.) BinaryLogicWrapper(operator.xor), BinaryLogicWrapper(operator.and_), BinaryLogicWrapper(operator.or_), UnaryLogicWrapper(operator.not_), ##███╗ ███╗ █████╗ ████████╗██╗ ██╗ ##████╗ ████║██╔══██╗╚══██╔══╝██║ ██║ ##██╔████╔██║███████║ ██║ ███████║ ##██║╚██╔╝██║██╔══██║ ██║ ██╔══██║ ##██║ ╚═╝ ██║██║ ██║ ██║ ██║ ██║ ##╚═╝ ╚═╝╚═╝ ╚═╝ ╚═╝ ╚═╝ ╚═╝ BinaryMathWrapper(operator.lshift), BinaryMathWrapper(operator.rshift), BinaryMathWrapper(operator.add), BinaryMathWrapper(operator.floordiv), BinaryMathWrapper(operator.mod), BinaryMathWrapper(operator.mul), BinaryMathWrapper(operator.pow), BinaryMathWrapper(operator.sub), UnaryMathWrapper(abs), UnaryMathWrapper(operator.neg), ): inscribe(F) ''' ██████╗ ███████╗███████╗██╗███╗ ██╗██╗████████╗██╗ ██████╗ ███╗ ██╗███████╗ ██╔══██╗██╔════╝██╔════╝██║████╗ ██║██║╚══██╔══╝██║██╔═══██╗████╗ ██║██╔════╝ ██║ ██║█████╗ █████╗ ██║██╔██╗ ██║██║ ██║ ██║██║ ██║██╔██╗ ██║███████╗ ██║ ██║██╔══╝ ██╔══╝ ██║██║╚██╗██║██║ ██║ ██║██║ ██║██║╚██╗██║╚════██║ ██████╔╝███████╗██║ ██║██║ ╚████║██║ ██║ ██║╚██████╔╝██║ ╚████║███████║ ╚═════╝ ╚══════╝╚═╝ ╚═╝╚═╝ ╚═══╝╚═╝ ╚═╝ ╚═╝ ╚═════╝ ╚═╝ ╚═══╝╚══════╝ ''' class Def(object): ''' Definitions are given by equations: name ≡ foo bar baz ... When a definition symbol is evaluated its body expression is put onto the pending expression. ''' # tribar = '\u2261' # '≡' def __init__(self, name, body): self.__doc__ = f'{name} ≡ {expression_to_string(body)}' self.__name__ = name self.body = tuple(iter_stack(body)) def __call__(self, stack, expr, dictionary): expr = list_to_stack(self.body, expr) return stack, expr, dictionary @classmethod def load_definitions(class_, stream, dictionary): ''' Given an iterable of lines (strings) and a dictionary put any definitions (lines with '≡' in them) into the dictionary. ''' for line in stream: if '≡' not in line: continue name, body = text_to_expression(line.replace('≡', '')) if name not in dictionary: inscribe(class_(name, body), dictionary) DEFS = '''\ Start with increment and decrement: -- ≡ 1 - ++ ≡ 1 + = ≡ eq + ≡ add > ≡ gt < ≡ lt >= ≡ ge <= ≡ le != ≡ ne <> ≡ ne % ≡ mod + ≡ add - ≡ sub * ≡ mul / ≡ floordiv div ≡ floordiv ? ≡ dup bool && ≡ nulco [nullary [false]] dip branch || ≡ nulco [nullary] dip [true] branch !- ≡ 0 >= <{} ≡ [] swap <<{} ≡ [] rollup abs ≡ dup 0 < [] [neg] branch anamorphism ≡ [pop []] swap [dip swons] genrec app1 ≡ grba infrst app2 ≡ [grba swap grba swap] dip [infrst] cons ii app3 ≡ 3 appN appN ≡ [grabN] codi map disenstacken at ≡ drop first average ≡ [sum] [size] cleave / b ≡ [i] dip i binary ≡ unary popd ccccons ≡ ccons ccons ccons ≡ cons cons clear ≡ [] swaack pop cleave ≡ fork popdd clop ≡ cleave popdd cmp ≡ [[>] swap] dipd [ifte] ccons [=] swons ifte codi ≡ cons dip codireco ≡ codi reco dinfrirst ≡ dip infrst dipd ≡ [dip] codi disenstacken ≡ ? [uncons ?] loop pop down_to_zero ≡ [0 >] [dup --] while drop ≡ [rest] times dupd ≡ [dup] dip dupdd ≡ [dup] dipd dupdip ≡ dupd dip dupdipd ≡ dup dipd enstacken ≡ stack [clear] dip first ≡ uncons pop flatten ≡ <{} [concat] step fork ≡ [i] app2 fourth ≡ rest third gcd ≡ true [tuck mod dup 0 >] loop pop genrec ≡ [[genrec] ccccons] nullary swons concat ifte grabN ≡ <{} [cons] times grba ≡ [stack popd] dip hypot [sqr] ii + sqrt ifte ≡ [nullary] dipd swap branch ii ≡ [dip] dupdip i infra ≡ swons swaack [i] dip swaack infrst ≡ infra first make_generator ≡ [codireco] ccons manual ≡ [] words [help] step pop neg ≡ 0 swap - not ≡ [true] [false] branch nulco ≡ [nullary] cons nullary ≡ [stack] dinfrirst of ≡ swap at pam ≡ [i] map pm ≡ [+] [-] clop popd ≡ [pop] dip popdd ≡ [pop] dipd popop ≡ pop pop popopop ≡ pop popop popopd ≡ [popop] dip popopdd ≡ [popop] dipd product ≡ 1 swap [*] step quoted ≡ [unit] dip range ≡ [0 <=] [1 - dup] anamorphism range_to_zero ≡ unit [down_to_zero] infra reco ≡ rest cons rest ≡ uncons popd reverse ≡ <{} shunt roll> ≡ swap swapd roll< ≡ swapd swap rollup ≡ roll> rolldown roll< rrest ≡ rest rest run ≡ <{} infra second ≡ rest first shift ≡ uncons [swons] dip shunt ≡ [swons] step size ≡ [pop ++] step_zero spiral_next ≡ [[[abs] ii <=] [[<>] [pop !-] ||] &&] [[!-] [[++]] [[--]] ifte dip] [[pop !-] [--] [++] ifte] ifte split_at ≡ [drop] [take] clop split_list ≡ [take reverse] [drop] clop sqr ≡ dup * stackd ≡ [stack] dip step_zero ≡ 0 roll> step stuncons ≡ stack uncons sum ≡ [+] step_zero swapd ≡ [swap] dip swons ≡ swap cons swoncat ≡ swap concat sqr ≡ dup mul tailrec ≡ [i] genrec take ≡ <<{} [shift] times pop ternary ≡ binary popd third ≡ rest second tuck ≡ dup swapd unary ≡ nullary popd uncons ≡ [first] [rest] cleave unit ≡ [] cons unquoted ≡ [i] dip unswons ≡ uncons swap while ≡ swap nulco dupdipd concat loop x ≡ dup i step ≡ [_step0] x _step0 ≡ _step1 [popopop] [_stept] branch _step1 ≡ [?] dipd roll< _stept ≡ [uncons] dipd [dupdipd] dip x times ≡ [_times0] x _times0 ≡ _times1 [popopop] [_timest] branch _times1 ≡ [dup 0 >] dipd roll< _timest ≡ [[--] dip dupdipd] dip x map ≡ [_map0] cons [[] [_map?] [_mape]] dip tailrec _map? ≡ pop bool not _mape ≡ popd reverse _map0 ≡ [_map1] dipd _map2 _map1 ≡ stackd shift _map2 ≡ [infrst] cons dipd roll< swons ''' if __name__ == '__main__': import sys J = interp if '-q' in sys.argv else repl dictionary = initialize() Def.load_definitions(DEFS.splitlines(), dictionary) try: stack = J(dictionary=dictionary) except SystemExit: pass