switch

Table of Contents

• switch
  • creating a switch
  • executing a case

 

switch

A library giving the ability to create code with switch-like statements.

In contrast to switch...case statements in C, there is no flow or fallthrough in this implementation. Executing a case will only ever execute that particular case, or the default case if there is no case with the specified identifier.

 

Creating a switch

The library returns a table which can be called as a function; taking a case table as its argument, and returning a new switch object with the specified case table.

Argument name	Type	Description
case table	table	a table of cases

 

Examples

• Create a new switch with an empty case table.

local myswitch = switch{}

• Create a new switch with a populated case table.

local myswitch = switch{
	[1] = "case one",
	[2] = "case two",
	default = "default case"
}

• Add a case to the case table.

myswitch[3] = "case three"

• Add a case as a function to the case table.

myswitch[4] = function()
	return "case four"
end

• Add a case with additional parameters to the case table.

myswitch[5] = function(...)
	return "case five\n"..save_table{...}
end

 

Executing a case

There are three methods for executing a case.

1. Calling the switch object's case function
2. Calling the switch object itself
3. Using array syntax on the switch object

Each methods requires passing at the very least one argument; the identifier for the case to execute.

Method 1 and 2 supports additional parameters; passed to the case if it is a function; or ignored if it is not.

If the case table has no case for the specified case identifier, the default case will be executed.

 

Examples

• Execute a case by calling 'case'.

LOG(myswitch:case(1))

• The function case supports additional arguments; passed to the case function for the specified case identifier.

LOG(myswitch:case(1, "argument1", "argument2", ...))

• Execute a case by simply calling the switch object. This is equivalent to using the function case above.

LOG(myswitch(1))

• This method also supports additional arguments.

LOG(myswitch(1, "argument1", "argument2", ...))

• Execute a case using array syntax. This is equivalent to the previous two methods, except it does not support passing of additional arguments like them.

LOG(myswitch[1])