Keg to Python Reference

It's official. Keg is now a transpiled language, as interpreting it was just too hard. Here is a guide of how everything now works

graph TB
First[Preprocessor] --> Second
Second[Uncompressor] --> Third
Third[Parser] --> Fourth
Fourth[Translator] --> Fifth
Fifth[Execution] --> Output

Command Glossary

Alphanumeric characters

Characters in the range of a-z and A-Z will be pushed as so:

letter()

As such, the program ABC would be transpiled as:

A(); B(); C()

And Hello World would become:

H(); e(); l(); l(); o(); space(); W(); o(); r(); l(); d()

This allows for letters to be redefined as macros if that makes sense. (More on that later)

Numbers in the range of 0-9 would follow as such:

0: zero()
1: one()
2: two()
3: three()
4: four()
5: five()
6: six()
7: seven()
8: eight()
9: nine()

Thenceforth, 89 would become:

eight(); nine()

Mathematical operators

Quite simple really:

+: add(stack.pop(), stack.pop())
-: minus(stack.pop(), stack.pop())
*: times(stack.pop(), stack.pop())
/: divide(stack.pop(), stack.pop())
%: modulo(stack.pop(), stack.pop())

Conditional Operators

I'mma start using a new way of writing these. All functions assume the parameters stack.pop(), stack.pop()

=: eq()
≠: nq()
>: gt()
<: lt()
≥: ge()
≤: le()
≬: g0()

Built-in FNS

These functions don't assume any parameters

!: length()
$: swap()
^: reverse()
:: duplicate()
": r_shift()
': l_shift()
,: nice()
.: raw()
?: _input()
~: random()
_: stack.pop()

If Statements

Unlike all prior sections, this section shan't be so brief. Why? Because the humble [...|...] isn't just a function you see.

The general form will become:

if bool(stack.pop):
	...
else:
	...

But what if there is only one section? (i.e. [...])

if bool(stack.pop()):
	...

But what if there is an empty ifTrue section but a filled ifFalse section? (i.e. [|...])

if bool(stack.pop()):
	pass
else:
	...

Although maybe this is more appropriate:

if not bool(stack.pop()):
	...

I mean, really, the only person bothering with this is those making transpilers.

For Loops

These are a bit harder, as, well, Keg loops are a little different. Given the normal counted loop (no vars, integer as condition):

for _ in _loop_eval(stack.pop())
	...

It is important to note that _loop_eval() is defined as such:

def _loop_eval(expr):
	if type(expr) in [int, chr]:
		return range(expr)
	else:
		return expr

But what if there are three parts? (i.e. (count|var|code))

for var in _loop_eval(count):
	code

But what if there isn't a loop condition?

length()
for _ in _loop_eval(stack.pop()):
	...

While loops

While loops are pretty similar to for loops, but easier in a way:

while bool(stack.pop()):
	...

But what if it is a post-test loop? (i.e. {...|P|...})

condition = True
while condition:
	...
	condition = bool(stack.pop())

Functions

The function @name n|...ƒ turns into:

def name(stack):
	temp = Stack()
	for _ in range(n): temp.push(stack.pop())
	...
	for item in temp:
		stack.push(item)

The function @name *|...ƒ gets turned into:

def name(stack):
	...

The function @name _|...ƒ gets turned into:

def name(stack):
	field = stack.pop()
	if type(field) in [int, float]:
		n = int(field)
	elif type(field) is str and len(field) == 1:
		n = _chr(field)
	else:
		n = len(field)
	
	temp = Stack()
	for _ in range(n):
		temp.push(stack.pop())
	
	...
	for item in temp:
		stack.push(item)

Escaping Characters

Escaping characters is an interesting problem:

stack.push("character")

or perhaps

escape(CHARACTER)

Comments

Comments aren't included in the transpiled program

The Register

Hmm. The register. Toggled with &, it will be turned into:

register()

The Reg Extension

Iota

iota(stack)

Sine

sine(stack)

Decrement

decrement(stack)

Nice Input

stack.push(_eval(_input()))

Apply to All

preprocesses as usual

Exclusive Range

Pop a, b and c and generate a range from a to b - 1 and return if c is in that range.

def excl_range(stack):
	query = stack.pop()
	values = [stack.pop(), stack.pop()]
	start, stop = sorted(values)
	range_object = range(start, stop)
	if query in range_object:
		stack.push(1)
	else:
		stack.push(0)

Inclusive Range

Pop a, b and c and generate a range from a to b and return if c is in that range.

def incl_range(stack):
	query = stack.pop()
	values = [stack.pop(), stack.pop()]
	start, stop = sorted(values)
	range_object = range(start, stop + 1)
	if query in range_object:
		stack.push(1)
	else:
		stack.push(0)

Generate Range

Pop a and b and generate a smart, inclusive range:

def smart_range(stack):
	values = [stack.pop(), stack.pop()]
	start, stop = sorted(values)
	range_object = range(start, stop + 1)
	for item in range_object:
		stack.push(item)

Item Split

This is an interesting one, as it requires type checking: nonetheless, here is what it probably transpile to:

def item_split(stack):
	item = stack.pop()
	_type = type(item)
	if _type is int:
		for number in str(item):
			stack.push(int(item))
	elif _type is str and len(item) == 1:
		for number in str(_ord(item)):
			stack.push(int(item))
	else:
		for value in item:
			stack.push(value)

Factorial

def factorial(stack):
	number = stack.pop()
	import math
	try:
		result = math.factorial(number)
	except Exception as e:
		result = "" #A whole lot of who knows what?
	stack.push(result)

Empty stack

def empty(stack):
	stack.clear()
	#Yes, it really is that simple.

Print All

def print_all(stack):
	for item in stack:
		print(item)

Keg+ Extension

Now, for the big guns: it's Keg+ time! This stuff isn't exactly defined yet, so this is new even for me. This is coming out soon, but I figured I might as well incorporate it into here right now.

So I guess each section will have the transpiled code and then a little description of what in the actual fr*ck everything does.

Push'n'Print

Includes characters in the range of ȦƁƇƉƐƑƓǶȊȷǨȽƜƝǪǷɊƦȘȚȔƲɅƛƳƵ

Pushes the specified letter to the stack and immediately prints it -- really helpful for those pesky restricted source challenges!

print(character)

Yes. It really is that easy.

Integer Scanning

The ‡ keyword is the new integer scanning operator, meaning that it will read through the code until a non-integer/decimal character is found. This is more a pre-processing command, but will be transpiled as so:

def integer(stack, number):
	stack.push(number)

Type Conversions

The commands ℤℝ⅍℠ (int, float, list and str respectively) all transpile as such:

def convert(stack, _type):
	item = stack.pop()
	try:
		item = _type(item)
	except:
		pass
	stack.push(item)

Case Conversion

The commands ⟰⟱⟷ represent uppercase, lowercase and switch case respectively:

def case_switch(stack, how):
	string = stack.pop()
	if type(string) is not string:
		stack.push(string)
		return
	if how == "upper":
		stack.push(string.upper())
	elif how == "lower":
		stack.push(string.lower())
	else:
		stack.push(string.swapcase())

Square Operator

² is probably found in most golfing languages, and it will square the top of the stack.

def square(stack):
	item = stack.pop()
	stack.push(times(item, item))

Take input as String

᠀ will take input as a string, ready to be casted as anything it needs to be casted as:

def string_input(stack):
	stack.push(input())

All(stack)

∀ returns 1 if all items on the big stack are "true"

def all_true(stack):
	if all(stack):
		stack.push(1)
	else:
		stack.push(0)

All equal

≌ pushes 1 if everything is the same (no popping)

def all_equal(stack):
	equal = 1
	last = None
	for item in stack:
		if last is None:
			last = item
			continue
		else:
			if item != last:
				equal = 0
				break
	stack.push(equal)

Summate stack

⅀ does this

def summate(stack):
	for item in stack:
		stack.push(add(stack.pop(), stack.pop()))

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