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0 pointsmianos1y ago0 comments

Of course I have. I worked in embedded systems at the start, but write one from scratch nope.

I do agree with you about the lack of traditional CS. Whenever I am parsing anything, I first reach for a FSM, and none of all the bullshit string copy, string trim, strim unpad, string unpad in the middle. I also know enough about modern lock free algorithms to know that some 10 minute scribble and a bunch of buzzwords does not scratch the surface.

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seanmcdirmid1y ago· 2 in thread

In general, scanning/lexing uses FSMs, parsing is done with push down automata (PDAs) (you need a stack to parse, you don’t really need a stack to scan).

mianosOP1y ago

You are making an example of my point? When parsing something like a comma separated list I generally don't get carried away with anything more with a switch/case state machine.

seanmcdirmid1y ago

You need a stack because you could have sub expressions that also have commas. You only get away with an FSM if your syntax doesn’t best anything.

So seeing “use FSM for parsing” will obviously raise lots of an eyes will CS people, especially compiler people.

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