ANN: Dogelog Runtime, Prolog to the Moon (2021)

[Mostowski Collapse]

There is a Python 3.8 compatible version here:

https://github.com/jburse/dogelog-moon/blob/main/devel/runtimepy/machine2.py

I have replaced match by if-then-else. So as to
be able to test with GraalVM. GraalVM is still faster
despite using if-then-else.

But GraalVM needs some time to JIT the code.
You need to make some cold runs before you
see kicking it being fast.

Mostowski Collapse schrieb am Mittwoch, 15. September 2021 um 20:48:31 UTC+2:
> And how do you iterate over the first n-1 elements 
> of a list with n elements? This is what my code does:
> i = 0 
> while i < len(term.args) - 1: 
> ____mark_term(term.args[i]) 
> ____i += 1 
> term = term.args[i]
> You can try yourself: 
> 
> % python3 
> >>> foo = ["a", "b", "c"] 
> >>> i = 0 
> >>> while i < len(foo) - 1: 
> ... print("mark_term", foo[i]) 
> ... i += 1 
> ... 
> mark_term a 
> mark_term b 
> >>> foo = foo[i] 
> >>> foo 
> 'c'
> alister schrieb am Mittwoch, 15. September 2021 um 20:41:12 UTC+2: 
> > On Wed, 15 Sep 2021 11:31:48 -0700, Mostowski Collapse wrote: 
> > 
> > > There is a further problem with this: 
> > > 
> > >> for i,term in enumerate(term.args): 
> > >> ____mark_term(term.args[i]) 
> > > 
> > > It should read: 
> > > 
> > > for i,help in enumerate(term.args): 
> > > ____mark_term(help) 
> > > 
> > > But then i isn't need. 
> > even Better (i had only skimmed the code as I was certain I would find 
> > this, it is probably the No. 1 thing new python programmers get wrong 
> > if your example is correct the it can be simplified even further to 
> > 
> > for help in term.args: 
> > mark_term(help) 
> > 
> > & if help does not get used after this loop then a comprehension is even 
> > better 
> > _ == [mark_term(help) for help in term.args] 
> > 
> > 
> > the underscore character is python convention for an unneeded place- 
> > holder variable. 
> > > 
> > > Mostowski Collapse schrieb am Mittwoch, 15. September 2021 um 20:22:50 
> > > UTC+2: 
> > >> Do you mean, replace this: 
> > >> i = 0 while i < len(term.args) - 1: 
> > >> ____mark_term(term.args[i]) 
> > >> ____i += 1 term = term.args[i] 
> > >> 
> > >> By this: 
> > >> 
> > >> for i,term in enumerate(term.args): 
> > >> ____mark_term(term.args[i]) 
> > >> 
> > >> This wouldn't be correct anymore. The recursive call is only for the 
> > >> arguments except for the last one one. 
> > >> alister schrieb am Mittwoch, 15. September 2021 um 20:17:23 UTC+2: 
> > >> > On Wed, 15 Sep 2021 18:23:10 +0200, Mostowski Collapse wrote: 
> > >> > 
> > >> > > I really wonder why my Python implementation is a factor 40 slower 
> > >> > > than my JavaScript implementation. 
> > >> > > Structurally its the same code. 
> > >> > > 
> > >> > > You can check yourself: 
> > >> > > 
> > >> > > Python Version: 
> > >> > > https://github.com/jburse/dogelog-moon/blob/main/devel/runtimepy/ 
> > >> > machine.py 
> > >> > > 
> > >> > > JavaScript Version: 
> > >> > > https://github.com/jburse/dogelog-moon/blob/main/devel/runtime/ 
> > >> > machine.js 
> > >> > > 
> > >> > > Its the same while, if-then-else, etc.. its the same classes 
> > >> > > Variable, Compound etc.. Maybe I could speed it up by some details. 
> > >> > > For example to create an array of length n, I use in Python: 
> > >> > > 
> > >> > > temp = [NotImplemented] * code[pos] 
> > >> > > pos += 1 
> > >> > > 
> > >> > > Whereas in JavaScript I use, also in exec_build2(): 
> > >> > > 
> > >> > > temp = new Array(code[pos++]); 
> > >> > > 
> > >> > > So I hear Guido doesn't like ++. So in Python I use += 
> > >> > > and a separate statement as a workaround. But otherwise, 
> > >> > > what about the creation of an array, 
> > >> > > 
> > >> > > is the the idiom [_] * _ slow? I am assuming its compiled away. Or 
> > >> > > does it really first create an array of size 1 and then enlarge it? 
> > >> > > 
> > >> > > Julio Di Egidio wrote: 
> > >> > <sniped due to top posting> 
> > >> > 
> > >> > this is probably a string contender 
> > >> > 
> > >> > i = 0 while i < len(term.args) - 1: 
> > >> > mark_term(term.args[i]) 
> > >> > i += 1 term = term.args[i] 
> > >> > 
> > >> > try replacing with something more pythonic 
> > >> > 
> > >> > for index,term in enumerate(term.args): 
> > >> > mark_term(term.args[i]) 
> > >> > 
> > >> > 
> > >> > & possibly go all the way to changing it into a comprehension 
> > >> > 
> > >> > there are other similar anti patterns throughout this code. 
> > >> > 
> > >> > any time you are manually keeping a counter as an index into a 
> > >> > list,tupple other iterable YOU ARE DOING IT WRONG! 
> > >> > 
> > >> > Do not write javascript in python, write python 
> > >> > 
> > >> > 
> > >> > 
> > >> > -- 
> > >> > Two percent of zero is almost nothing. 
> > >> > 
> > >> > 
> > >> > 
> > >> > 
> > >> > -- 
> > >> > Whoever dies with the most toys wins. 
> > -- 
> > Pie are not square. Pie are round. Cornbread are square.