Strange Ruby String Selection
The string in question (read from a file):
if (true) then { _this = createVehicle ["Land_hut10", [6226.8901, 986.091, 4.5776367e-005], [], 0, "CAN_COLLIDE"]; _vehicle_10 = _this; _this setDir -2.109278; };
Retrieved from a large list of similar (all same file) strings via the following:
get_stringR(string,"if","};")
And the function code:
def get_stringR(a,b,c) b = a.index(b) b ||= 0 c = a.rindex(c) c ||= b r = a[b,c] return r end
As so far, this works fine, but what I wanted to do is select the array after "createVehicle", the following (I thought) should work.
newstring = get_string(myString,"\[","\];")
Note get_string is the same as get_stringR, except it uses the first occurrence of the pattern both times, rather then the first and last occurrence.
The output should have been:
["Land_hut10", [6226.8901, 986.091, 4.5776367e-005], [], 0, "CAN_COLLIDE"];
Instead it was the below, given via 'puts':
["Land_hut10", [6226.8901, 986.091, 4.5776367e-005], [], 0, "CAN_COLLIDE"]; _vehicle_10 = _this; _this setDir
Some 40 characters past the point it should have retrieve, which was very strange... Second note, using both get_string and get_stringR produced the exact same result with the p开发者_如何学运维arameters given.
I then decided to add the following to my get_string code:
b = a.index(b) b ||= 0 c = a.index(c) c ||= b if c > 40 then c -= 40 end r = a[b,c] return r
And it works as expected (for every 'block' in the file, even though the strings after that array are not identical in any way), but something obviously isn't right :).
You want r = a[b..c] instead of r = a[b,c].
Difference is: b..c = start from b, go to c, while b,c = start from b and move c characters to the right.
Edit: You don't have to/shouldn't escape the [ and ] either, because you are using strings and not regexen. Also, you have to take the length of the end ("];") into consideration, or you will cut off parts of the end.
def get_stringR(a,b,c)
bp = a.index(b) || 0
cp = a.rindex(c) || bp
r = a[bp..cp + c.size - 1]
return r
end
def get_string(a,b,c)
bp = a.index(b) || 0
cp = a.index(c) || bp
r = a[bp..cp + c.size - 1]
return r
end
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