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digitalmars.D.learn - Finite state machine in D

reply Druzhinin Alexandr <news digitalmars.com> writes:
Hello
Could someone help me with FSM (like boost MSM but simpler and in D of 
course) - where should I start from? I found good paper about FSM 
implementation in c++ (with type list and so on), but I'm not sure it is 
applicable in D. What is the D-way to implement fsm with code generation?
Sep 26 2012
parent reply Mirko Pilger <pilger cymotec.de> writes:
 What is the D-way to implement fsm with code generation?


you might have a look at ragel:

http://www.complang.org/ragel/
Sep 27 2012
parent reply Druzhinin Alexandr <news digitalmars.com> writes:
27.09.2012 14:48, Mirko Pilger пишет:

 What is the D-way to implement fsm with code generation?


 you might have a look at ragel:

 http://www.complang.org/ragel/


I had. It's good but is too fat for my purpose - simple fsm 
implementation in D without third party's instruments (for simple use). 
My question was inspired when I saw several fsm implementation in c++, 
but I didn't find D implementation to compare with. And now I'm writing 
my own. This writing seems to be very useful - I've found new advantages 
of D over C++ =)
Sep 27 2012
parent reply Philippe Sigaud <philippe.sigaud gmail.com> writes:
On Thu, Sep 27, 2012 at 10:15 AM, Druzhinin Alexandr
<news digitalmars.com> wrote:

 27.09.2012 14:48, Mirko Pilger =D0=BF=D0=B8=D1=88=D0=B5=D1=82:


 What is the D-way to implement fsm with code generation?






I'm not sure you need code generation. Using D functions literals or
closures already gives you a good part of a FSM:

States are functions, that accept a current 'payload' and return a
tuple consisting of another function and the new payload.
The FSM driver just call the current state on the current payload,
stores the new stat/payload pair and loop until it reaches a terminal
state.

I can search at home to see what I have (if I kept anything), if
you're interested. It's a FSM in 10-20 lines of code, IIRC.

If you really want code generation, could you give us some use case?
std.regex contains a compile-time regex engine that is, in a way, a
FSM on steroids. I have a parser generator project on github that also
does code generation, but both modules are for a particular type of
automata: parsers/matchers, not a generic FSM.
Sep 27 2012
parent reply Druzhinin Alexandr <news digitalmars.com> writes:
27.09.2012 18:15, Philippe Sigaud пишет:

 I'm not sure you need code generation. Using D functions literals or
 closures already gives you a good part of a FSM:

 States are functions, that accept a current 'payload' and return a
 tuple consisting of another function and the new payload.
 The FSM driver just call the current state on the current payload,
 stores the new stat/payload pair and loop until it reaches a terminal
 state.

 I can search at home to see what I have (if I kept anything), if
 you're interested. It's a FSM in 10-20 lines of code, IIRC.


yes, I'm interested. Thanks in advance.

What about code generation - I just want to learn how to do it, so
Sep 27 2012
parent reply Philippe Sigaud <philippe.sigaud gmail.com> writes:
On Thu, Sep 27, 2012 at 2:39 PM, Druzhinin Alexandr
<news digitalmars.com> wrote:


 yes, I'm interested. Thanks in advance.


Here is an example:

http://dpaste.dzfl.pl/81a63163



 What about code generation - I just want to learn how to do it, so


Seeing your code in another thread, yes code generation could help
here. I have a template tutorial (a bit light on code generation) that
might help you on this.

https://github.com/PhilippeSigaud/D-templates-tutorial/blob/master/dtemplates.pdf?raw=true

(this will download a pdf)



 Sep 27 2012



  parent  Druzhinin Alexandr <news digitalmars.com>  writes:


28.09.2012 01:24, Philippe Sigaud пишет:

 Here is an example:

 http://dpaste.dzfl.pl/81a63163


it's really interesting for me.


 Seeing your code in another thread, yes code generation could help
 here. I have a template tutorial (a bit light on code generation) that
 might help you on this.

 https://github.com/PhilippeSigaud/D-templates-tutorial/blob/master/dtemplates.pdf?raw=true

 (this will download a pdf)


Oh, there's a lot to know. ) Thank you!



 Sep 29 2012