So for the past few months, I have been grappling with functions such as string.sub, string.gsub, string.find, string.gfind, string.match,string.gmatch, and string.format, but never really understood them entirely, I have had some experience with string.sub, string.gsub, and string.find using patterns instead of the init string. For example, a couple months back, I tried making a typewriter gui using string.sub:
local text = "Some Demo Test" local textlabel = script.parent for i = 1, #text do textlabel.Text = string.sub(text,1,i) wait() end textlabel:Destroy()
and did some reseach on the lua users wiki, lua.org, and the roblox wiki for how to properly use these functions. Eariler today I tried experimenting with string.find and string.sub
local randomstring = "My Friend Chuck Says Hi" print(string.sub(randomstring,2,5))--prints the 2nd, 3rd, 4th, and 5th letters of randomstring local d = "%u+" print(string.sub(randomstring,string.find(randomstring,d)))--prints first few uppercase letters local d2 = "%w+" print(string.sub(randomstring,string.find(randomstring,d2)).."---------d2")--prints the first chunk local d3 = "%w+%s+" print(string.sub(randomstring,string.find(randomstring,d3)).."---------d3")
but apart from those three, I really don't know much more about these functions that show up time and time again in scripts for admin commands, emotes through text, and etc. So if anyone can give me a good definition of what they do and an example of how they work, that would be much appreciated
Alright, it's probably best to go through these one at a time.
Note: The parameters I'm using aren't the officially used ones on the wiki, but it's pretty obvious what I mean and some of the wiki parameter names (
s) aren't very helpful.
string.find(target, search, startPoint):
You seem to already have have a good idea of what this does, but it searches for the regular expression
search in the string
target and returns the starting and ending position of the first one it finds. You can use
startPoint to decide where in the string to start looking. It's not (generally) particularly useful unless coupled with
string.sub(target, start, ending):
Again, you probably know what this is, but it returns a substring of
target starting at character
start and ending at character
ending. It's useful for trimming off part of a string that you don't need.
string.gsub(target, search, replacement):
Despite the similarity in name to
string.sub, this is actually a very different function. It looks for each case of regular expression
search and replaces that with
replacement. It's super useful for a bunch of stuff, including removing all white-space, replacing numbers with their written-out forms, etc.
This isn't a thing on the Roblox wiki, and while it may be a thing in pure lua, should not be used in Roblox projects.
string.match(target, search, startPoint):
Parameters look pretty similar to
string.find(), right? That's because it's the same thing, except it returns the string it finds instead of the starting and ending points of those strings. This can be used to make the code posted in your original post cleaner; instead of
string.sub(randomstring,string.find(randomstring,d2)) you can simply do
string.match(randomstring,d2). Very useful with regular expressions.
This returns a function you can iterate over (like
ipairs). Each iteration is a
string.match(target, pattern) starting off its search where the last iteration left off. Useful for looking for multiple cases of a regular expression (like all words in a sentence).*
... represents the targets that are formatted by the
formattingString. For information on what
formattingString can be, check the Lua site's information on it after the sixth code-block. (I'll be honest, I don't use/understand this one much, but the site has good information on it.)
Edit: * This particular example would be done like below:
for word in string.gmatch("h0wdy pardners th1s is epi<", "[^%s]+") do -- [^%s]+ represents multiple non-space characters print(word) end