174 posts
Posted 09 January 2013 - 07:55 PM
How can i make a Turtle program that needs a parameter set when you run it? Something kind of like the GPS Host program that needs you to input the x y z values.
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[Lua][Turtle] Making a program that needs parameters
Started by jewelshisen, 09 January 2013 - 06:55 PM
7508 posts
Australia
Posted 09 January 2013 - 07:58 PM
use the … operator? ( i think its an operator, just had a mental blank )
example:
this puts all the arguments into a table.
example:
local runtimeArgs = { ... }
this puts all the arguments into a table.
174 posts
Posted 09 January 2013 - 08:01 PM
Ah! Thank you! I'm still learning lua and CC so it is taking me some effort. Can you also just store it as a normal variable? For instance if you only need one argument?
7508 posts
Australia
Posted 09 January 2013 - 08:04 PM
yes you can… you can do this
however I suggest that you do this (for reasons you will be able to tell
local args = ...however I suggest that you do this (for reasons you will be able to tell
local args = { ... }
if #args ~= 1 then
print( "Usage: program <param1>" )
error()
end
-- then if you just want to get it out of the table
args = args[1]
174 posts
Posted 09 January 2013 - 08:06 PM
Ah thank you! Tiny question though: What does ~= mean??
7508 posts
Australia
Posted 09 January 2013 - 08:08 PM
not equal to… its equivalent to
if not #args == 1 then
7508 posts
Australia
Posted 09 January 2013 - 08:11 PM
I good resource for learning is here it covers everything Lua.
7508 posts
Australia
Posted 09 January 2013 - 08:36 PM
something else notable with the '…' is this:
this means that the function can accept any amount of arguments.
local function doSomething( ... )
print( table.concat( { ... }, " " ) )
end
doSomething( "Hello" )
doSomething( "Hello", "How" )
doSomething( "Hello", "How", "Are" )
doSomething( "Hello", "How", "Are", "You" )
this means that the function can accept any amount of arguments.