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Well (particularly @Marc-Clifton - you might get a kick out of this)
I made an assembler for my little regex runner virtual machine.
now instead of regex you can write asm code directly to the fekking thing
; lex identifier
save 0
set "A".."Z", "_", "a".."z"
loop:
split idpart, done
idpart:
set "0".."9", "A".."Z", "_", "a".."z"
jmp loop
done:
save 1
match 0
instead of ([A-Z_a-z][0-9A-Z_a-z]*) which would give you the same code =P
however, you can at least do things with it you can't make with regex, but i'm not sure how useful that is in practice. If you really hate regex though you can use asm.
Next up, maybe I'll make a C++ -> asm compiler for it. 
Real programmers use butterflies
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honey the codewitch wrote: now instead of regex you can write asm code directly to the fekking thing
Very cool - speaks to my inner child, as after learning BASIC on a PDP-11 I really cut my programming teeth on years of assembly language programming. 
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Very similar with me, except later. I learned basic on an Apple II, followed by 6502 bytecode before I discovered the mini assembler.
I'll post an article about it later when i post lexly
Real programmers use butterflies
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I made a linker for this.
I actually made a linker for this.
Reason being is so you can intersperse your hand written assembly code with compiled regex expressions.
somebody stop me!
Real programmers use butterflies
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But it's ok - the £2,400,000 of public money they spent refurbishing Frogmoor Cottage will be repaid.
Harry will pay it off at £5 per week from his unemployment benefit.
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
AntiTwitter: @DalekDave is now a follower!
modified 19-Jan-20 7:12am.
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Given the speedy Megxit outcome, the Queen should have negotiated Brexit.
modified 19-Jan-20 7:12am.
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OriginalGriff wrote: Harry will pay it off at £5 per week from his unemployment benefit.
Are you sure he can afford that much? Getting used to living on a budget isn't easy!
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
modified 19-Jan-20 7:12am.
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Pratsit, more like.
Why didn't Charles think of doing this, decades ago? I'm sure ER indoors wouldn't have minded handing the reigns over to Anne.
I wanna be a eunuchs developer! Pass me a bread knife!
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Mark_Wallace wrote: Pratsit, more like
For me it sounds more like parasit
M.D.V. 
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
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Teach endlessly for coin (5)
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eDUCATe =>> DUCAT
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
AntiTwitter: @DalekDave is now a follower!
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ya 
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No. I don't own 750 Rubik Cubes.
I could build a very pixelated image of John Cena out of one though*
* If I owned one Rubik Cube, and I had any idea who John Cena is / was / will be. Which I don't.
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
AntiTwitter: @DalekDave is now a follower!
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Again with the logic issues!
It's a hideously inefficient and imprecise way to make a picture, but, for whatever peculiar reasons, he and his parents find logic in this inefficiency and imprecision (which will absolutely not get him into art school).
Are crayons banned, in his house, to prevent him drawing on the walls (which is tricky to do with Rubik's cubes)?
I wanna be a eunuchs developer! Pass me a bread knife!
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Pfft ... he's got a cheat sheet in front of him. He's a good "cuber", but probably a lousy artist (software)
It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food
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In C# I took my lex from .045 msec to .028 msec by changing the lists i was using to arrays.
This despite the fact that there were no reallocs happening in those lists (i already checked)
_Fiber[] currentFibers, nextFibers, tmp;
int currentFiberCount=0, nextFiberCount=0;
is simply faster than this
IList<_Fiber> currentFibers,nextFibers,tmp;
Conventional wisdom is lists are about as good as arrays perfwise as long as your capacity is high enough.
Conventional wisdom can get bent
Real programmers use butterflies
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That probably hasn't been true from the time CPUs got caches. Stroustrup himself says as much.
Mircea - I would put a smart quote in my signature if I wouldn't be so lazy and if smart quotes wouldn't be so overused.
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Well, Microsoft's .NET soothsayers would tell him otherwise, but he's right.
Adding: After reading that link it looks like Bjarne and I aren't talking about quite the same thing.
Basically if this was C++ and not C# I'd be complaining that arrays are faster than std::vector, not lists
Real programmers use butterflies
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Reference Source. Makes some sense. You're saving 17 microseconds and all of those checks and calls cost some amount of time. My thoughts have always been that lists are better as a default because you can abstract them (e.g. IList<t>) and you don't need to worry about bounds, while arrays are better when optimizing critical sections for performance (indirection has a cost).
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This is one of the few areas where i need every microsecond i can get.
It's a virtual machine that runs a regular expression match as per here:
Regex as a Tiny "Threaded" Virtual Machine[^]
It seems trivial but this code itself ends up being part of an inner loop of an inner loop when it's being driven by a parser.
It needs to be as efficient as it can be.
My hope in using lists initially was that the framework would minimize the impact of bounds checking in the ngen'd corlib beyond what arrays already do internally but i guess that was wishful thinking
Real programmers use butterflies
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array is not only supposed to predictively as fast as foreach loop on list
but I am not sure I quite believe it...
The difference is only very minor though.. and would be important if your statement each iteration is quite minimal...
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foreach itself has some performance issues as it requires object creation.
I need to eke every clock cycle I can out of this routine.
Normally I only optimize when i can make algorithmic improvements, but my algo is already tight for what it does.
Sometimes even in the days of powerful computers, we still need to bit twiddle every once in awhile. Lexer routines are a good example of where.
Real programmers use butterflies
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The goal of this is to produce a small program to solve a physical problem with numerical data. An electron of
charge −e and mass me is moving at a speed v(t = 0) = vex in the plane Oxy between the two plates of a capacitor.
The field is given by E= Eey. The only force is Lorentz F=qE. Plot the trajectory of this electron.
Python code: plot the trajectory of this electron; use matplotlib.pyplot to plot and scipy.integrate.ode
to solve the problem.
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