Difference between revisions of "Case"

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== Description ==
 
== Description ==
  
Calling case returns a case closure with one defined method, [[case.on|on]].  This closure can stand in place of complicated if-elseif code and functions analogously to the C language switch case construct except that it can be called anywhere once defined.  The first parameter passed to the [[[case.on|on]] method selects a function from the initial case table and calls it with the remaining parameters passed through.
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Calling case returns a case closure with one defined method, [[case.on|on]].  This closure can stand in place of complicated if-elseif code and functions analogously to the C language switch case construct except that it can be called anywhere once defined.  The first parameter passed to the [[case.on|on]] method selects a function from the initial case table and calls it with the remaining parameters passed through.
  
 
== Alternative Calling Patterns ==
 
== Alternative Calling Patterns ==

Revision as of 11:59, 2 November 2010

Calling Pattern

Call

local c = sl.case(casetable)

Args

casetable is a table, where keys are any type and values are functions

Results

c is a case closure

Closure Methods

Example Usage

local t = 
  {
  [1]     = function(...) local a={...} print('a') print(a[a[5] ]) end,
  ['1']   = function(...) local a={...} print('b') print(a[a[4] ]) end,
  bye     = function(...) local a={...} print('c') print(a[a[3] ]) end,
  default = function(...) local a={...} print('d') print(a[a[2] ]) end,
  }
local c = sl.case(t)
local z = 'bye'
c.on(z,2,3,4,5,6)
--> 'c'
--> 5

Description

Calling case returns a case closure with one defined method, on. This closure can stand in place of complicated if-elseif code and functions analogously to the C language switch case construct except that it can be called anywhere once defined. The first parameter passed to the on method selects a function from the initial case table and calls it with the remaining parameters passed through.

Alternative Calling Patterns

Upon Error

See Also