Post by Internet Janitor in Lil Programming Questions

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Internet Janitor2 years ago (4 edits) (+2)

There's a lot of room for improvement in Lil performance. The each loop in your example is particularly expensive because "each" is a map operation yielding a result list, range eagerly creates an entire list, and each loop body is executed in its own scope. Contrast with "while", which is considerably faster due to involving less bookkeeping and keeping much less in memory at once:

while x<1000000
  x:1+x
end

Or, when it's possible, just using the natural "conforming" over lists:

1+range 1000000

Performance for each over a huge list is particularly bad in c-lil; I'll do some investigating.

gcanyon2 years ago

Interesting -- I'm not terribly familiar with list generation: I've played with Python, so I know it's a thing, but LiveCode has nothing like it built in, and I would never do something like

repeat with i = 1 to 1000000
    put i,"" after aList
end repeat
repeat for each item i in aList
    -- do something
end repeat

I just checked and found that the while loop was even slower :-)

I'm not sure this accomplishes the same task, albeit that the task is synthetic in the first place, but in any case, this is about 20x faster:

on click do
range 10000000
 alert["Done!"]
end

Internet Janitor2 years ago (1 edit) (+1)

Oh, there's one other thing I should note that's probably making us talk past one another somewhat: Lil in Decker is deliberately capped at a specific number of "ops" (VM bytecode steps) per "frame" (display updates at 60fps) . This is an arbitrary creative constraint intended to help decks behave more consistently across different machines with wildly different levels of performance. The "FRAME_QUOTA" constant in the JavaScript implementation controls this cutoff.

gcanyon2 years ago

Oh, HA! Okay, that makes sense. "constant in the JavaScript implementation" -- meaning updating it requires rebuilding Decker from source? Or is it configurable?

Internet Janitor2 years ago

You can rebuild from source, or, in a web build, just open the file in your favorite text editor, search for "FRAME_QUOTA", and tweak as desired. I may raise the limit and/or make it configurable at runtime in the future.

OXTPaul1 year ago (1 edit)

LiveCode script (and the GPLv3 community fork OpenXTalk) has arrays which can be considerably faster then using comma-seperated-values for text container 'lists' (but when I do I use tab as a delimiter).
Also LC / OXT has a second language, the Extension Builder lang for making 'Widgets' and wrapping external code libraries, which does have an actual List type where the ordered elements can be of any type, Text, Numbers, JSON, Java, or C and ObjC types, Pointers, etc.

itch.io

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