# Metadata
Platforms: desktop, server, mobile OS: mac, windows, linux, ios, android Introduced: 1.0 Security:
# Syntax
the param of parameterNumber
# Params
- parameterNumber : A non-negative integer.
# Examples
param(3) -- returns the third parameter
param(0) -- returns the handler name
# Description
Use the param function within a handler to get the value of a parameter when you don't know in advance how many parameters will be pass to the handler.
Usually, you assign names to parameters in the first line of a function handler or message handler. For example, the following function assigns three parameters, which are multiplied together:
function product firstFactor,secondFactor,thirdFactor return firstFactor * secondFactor * thirdFactor end product
But if you want to multiply all the numbers passed to the function handler together, you don't know ahead of time how many parameters will be passed, so you can't assign a parameter name (such as firstFactor) to each one in the first line of the function handler. In this case, you can use the param function to use each parameter without needing to assign it a name:
function product put 1 into total repeat with nextFactor = 1 to the paramCount multiply total by param(nextFactor) end repeat return total end product
LiveCode evaluates the parameters before passing them. So if you call myHandler with the following statement:
myHandler 1+1,"A","Hello" && "world"
2, A, and "Hello World".
# Tags
# See