Module:Protect/doc

This metamodule simplifies error handling in other modules. It transforms a function, which may throw an error, into a function, which returns a specified error message in that case.

Usage

local protect = require('Module:Protect')
local protectedFunc = protect(func, errFormat, options)

Arguments

• func
  

  Function to be transformed.

• errFormat
  

  (default:

  'Error: %s'
  

  )

  Custom error message.

  Use

  '%s'
  

  to include the message from a caught error.

• options
  

  – optional table with the following fields:

  • raw
    

    (default: false)

    If true, then

    errFormat
    

    will be used as is, otherwise it will be wrapped inside a tag <strong class="error">.

  • removeLocation
    

    (default: true)

    If true, removes location information from caught error messages.

Return value

The resulting

protectedFunc

is a function, which calls the original function

func

, passing all arguments to it, and returns all its return values. If

func

throws an error, the specified error message is returned instead.

Example

local protect = require('Module:Protect')

local p = {}

function p.main(frame)
    if not frame.args[1] then
        error('missing argument')
    end
    return frame.args[1]
end

p.main = protect(p.main)

return p

Invoking the main function without arguments will output: