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FINALLY! An NFA regex implementation, explained and not in some fruity language like python, but in good old C code!
wregex - How Regular Expression Engines Work[^]
I can finally implement unicode regex matching. Onward rolex 2!
Edit: Oh my this is fascinating. I just found a follow up implementing an NFA regex engine as a kind of tiny virtual machine with "threads".
Regular Expression Matching: the Virtual Machine Approach[^]
My turn! Let me see what I can do with this idea. *giddy*
Steve Wozniak is the only thing at Apple that isn't evil.
modified 13-Jan-20 15:11pm.
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You live in an interesting world 
"We can't stop here - this is bat country" - Hunter S Thompson - RIP
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it's a bit nerdy here. 
Steve Wozniak is the only thing at Apple that isn't evil.
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honey the codewitch wrote: not in some fruity language like python
/ravi
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Nice. Regex's, DFA's and NFA's are some of my favorite things.
You must have a lot of time on your hands to be doing such fun stuff...
Good for you!
#SupportHeForShe
Government can give you nothing but what it takes from somebody else. A government big enough to give you everything you want is big enough to take everything you've got, including your freedom.-Ezra Taft Benson
You must accept 1 of 2 basic premises: Either we are alone in the universe or we are not alone. Either way, the implications are staggering!-Wernher von Braun
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I wrote a DFA based lexer generator which i use in my parsers, but I've been using gplex lately for lexing as i need unicode support and i don't think DFA regex engines can handle unicode.
I tried implementing unicode in my DFA based lexer and it choked during the powerset construction. Unicode just has too many characters. Maybe there's a better way but it's beyond me so I'm looking at the NFA approach which i've never done before.
I hate this terminology because all NFAs are DFAs but "NFA regex" is kind of a misnomer. A backtracking regular expression engine that usually uses a kind of bytecode interpreter rather than simple pattern matching to run its matches... dumb that it's called NFA regex but there it is.
Steve Wozniak is the only thing at Apple that isn't evil.
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Asked for Arnold Schwarzenegger action figures.
They were at aisle B, back.
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...
What do you get when you cross a joke with a rhetorical question?
The metaphorical solid rear-end expulsions have impacted the metaphorical motorized bladed rotating air movement mechanism.
Do questions with multiple question marks annoy you???
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And the Oscar goes to... Sander Rossel! 
/ravi
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No, it was Stallone in "Oscar".
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Stole for Farcebook. Tried to tag you, buy couldn't.
/ravi
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DD? Is that you? Is it Friday?
I wanna be a eunuchs developer! Pass me a bread knife!
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I bought this book the other day (I had read a brief excerpt long ago) and it is really fantastic.
I love a retrospective on how technologies came together and this is written by a very good writer who brings the subject to life. It's only $1.99 on kindle so a great value.
The Chip: How Two Americans Invented the Microchip and Launched a Revolution, T.R. Reid, eBook - Amazon.com[^]
It explains the main challenge to circuit building even after transistors were invented:
from the book: “For some time now,” wrote J. A. Morton, a vice president of Bell Labs, in an article celebrating the tenth anniversary of the transistor, “electronic man has known how ‘in principle’ to extend greatly his visual, tactile, and mental abilities through the digital transmission and processing of all kinds of information. However, all these functions suffer from what has been called ‘the tyranny of numbers.’
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INteresting. Why Z80? Do you have experience with it from the past? Just curious.
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Why not? It's a damn good little processor, and very flexible.
"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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OriginalGriff wrote: Why not?
Only reason I can think of is that it may be difficult to program, right? Need equipment that is a bit more expensive maybe? Not sure.
And by difficult to program, I mean more difficult than newer chips like ATMega line (think Arduino), etc.
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No the board runs CP/M and you can code in Assembler, Basic and I think Forth.
Did a little mechanic work today.
Put a rear end in a recliner!
JaxCoder.com
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Mike Hankey wrote: No the board runs CP/M and you can code in Assembler, Basic and I think Forth
Very interesting.
What is the hardware programmer like? Is it expensive? Can you (did you) build one yourself? Is it just a serial interface? Is there a hardware programmer with USB interface?
Millions of questions here. 
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Here's the Hackaday link to the project Z80-MBC2: 4ICs homemade Z80 computer | Hackaday.io[^].
Quote: The MCU Atmega32A is used as universal I/O subsystem, as Eeprom, and as reset and 4/8MHz clock generator for the Z80 CPU.
Inside the Atmega32A it is flashed an Arduino bootloader taken from here, and it is possible to use the Board Manager of the Arduino IDE to "import" it.
raddevus wrote: Can you (did you) build one yourself?
I bought the board and am soldering components, a lot of the are on order so it will be a while before I can update.
raddevus wrote: Is it just a serial interface?
There is a community that offers other boards for this chip/board but I'm at an early stage so if I can get it running on serial I'll be happy and then go from there.
raddevus wrote: Is there a hardware programmer with USB interface?
I have a hardware programmer to program the ATMega32A, I work with Atmel devices a lot. I use an USBTiny programmer but clones are very cheap on Fleabay. USBTiny USBtinyISP AVR ISP programmer for Arduino bootloader Meag2560 uno r3 711331264374 | eBay[^]
Did a little mechanic work today.
Put a rear end in a recliner!
JaxCoder.com
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If you really need it, and can find an old 8" floppy drive somewhere, I can hook you up with a PL/I compiler for CP/M.
Software Zen: delete this;
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Thanks, appreciate it I'll keep that in mind!
It's been 6 months since I joined the gym and there's been no progress. I'm going there tomorrow in person to find out what's really going on!
JaxCoder.com
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Worked with it some when I first started computing, back in the dark ages.
I loved programming them back then and thought it would be fun to do some assembly and maybe even (shudder) some basic.
Did a little mechanic work today.
Put a rear end in a recliner!
JaxCoder.com
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I'm more a 6502 type, the Z80 powered the Sinclair line of home PC's I was more a Commodore type...
Played with 6502 assembler back in college. Went from there to PIC...
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Got the Commodore in early 80s, loved that machine. Wrote a sprite editor in assembler.
Had a lot of problems with the tape drive, could never get it to work reliably.
Did a little mechanic work today.
Put a rear end in a recliner!
JaxCoder.com
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