How to detect blocks of text

Question

Is it possible to get block of text inbetween two markers? I am trying to write my version of LOLCODE and i want to make if statement - then i ran into this problem.

Basic thing is, that i want to do this:

IS #DIR = 5
    YUP
 -if statement suceeded, execute code here-
    NOPE
 -if statement returned false, execute code here
BYE

Explanation: This code should check if variable #DIR is equal to five, if yes then execute code in YUP block, if not - execute code in NOPE block.

My question is : How to read this from text file and execute proper block of code using java?

@MarkoTopolnik Awesome, thanks but do you have any ideas on what parser should i use - or shall i make one? — themorfeus, Jul 17 '12 at 20:25
Make one, but not from scratch. There are libraries that let you start from a BNF and they take care of the rest. `antlr` is one such library, very popular. — Marko Topolnik, Jul 17 '12 at 20:29

score 3 · Answer 1 · edited May 23 '17 at 12:24

3

Try a regular expression like this:

searchText.matches("^\\s*IS\\s+(#\\w+)\\s*=\\s*(\\w+)\\s*")

This expression only evaluates The first line "IS #DIR = 5" but you can complete it is only the idea to do it ;)

Edit: Maybe this link can help you if the inner blocks of code are Java: Dynamic code execution

edited May 23 '17 at 12:24

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answered Jul 17 '12 at 20:24

PaNaVTEC

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This is the stuff i know. Only thing i cant figure out is how to run a proper block of code. – themorfeus Jul 17 '12 at 20:28
I edited the answer for include the link of Dynamic code execution – PaNaVTEC Jul 17 '12 at 20:32
Regex is useless for parsing nested structures. – Marko Topolnik Jul 17 '12 at 20:42
Thanks, but i'll use Marko's advice on making parser :) – themorfeus Jul 18 '12 at 11:09

How to detect blocks of text

1 Answers1