On 6/29/19 8:39 AM, josé mariano wrote:
Dear all,
I'm sure that this subject has been addressed many times before on this forum,
but my poor knowledge of English and of computer jargon and concepts results on
not being able to find the answer i'm looking for when I search the forum.
So here is my problem: I have this open source project for the scientific
community were i want to duplicate an old MS-DOS application written in
Fortran. I don't have the source code. The idea is to re-write the software in
Python. Originally, the old application would would need to input files: one
config file, written with a specific format (see below) and a second one, the
so-called scrip file, that defines the sequence of operations to be performed
by the main software, also written in a specific format.
To make the transition to the new application as painless as possible to the
users, because most of them have their collection of scrips (and settings)
developed over the years and are not willing to learn a new script language, I
would like to make the new app 100% compatible with the old input files.
The operation of the new software would be like this: From the shell, run
"my_new_software old_script_file.***". The new software would load the
old_script, parse it (?), set the internal variables, load the script and run it.
So, to get to my questions:
- To load and read the config file I need a parser, right? Is their a parser
library where we can define the syntax of the language to use? Are there better
(meaning easier) ways to accomplish the same result?
- For the interpretation of the script file, I don't have any clue how to
this... One important thing, the script language admits some simple control
flow statements like do-wile, again written using a specific sintax.
Thanks a lot for the help and sorry for the long post.
Mariano
Example of a config (settings) file
========================
.....
CONDAD -11
BURAD2 4 SALT1 1.0 KNO3
ELEC5 -2.0 mV 400 58 0. 0
.....
Example of a script
===================
!Conductivity titration
cmnd bur1 f
set vinit 100
set endpt 2000
set mvinc 20
set drftim 1
set rdcrit cond 0.5 per_min
set dosinc bur1 0.02 1000
set titdir up
titratc cond bur1
I'll just add a general comment here.
Yes, you do need a parser and that parser should be a separate module or
separate class from the rest of your program. As Thomas Jollans wrote,
str.split() might be enough to do all of the string twiddling for you.
If you have a separate class (or group of classes) that produces a
configuration object and a script object then, if you discover examples
of configuration or script files that you weren't aware of when you
wrote the code, then may you only need to modify your parser code and
may not have to modify your script execution logic.
Finally, I want to say that I wish everyone in the U.S. had as much
command of English as you do. Si pudiera hablar español tan bien como
usted habla inglés, estaría muy feliz. (You should have seen what that
looked like before I applied Google Translate :)
Alan
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