This is the documentation page for Module:Protect
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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 edit source
 local protect = require('Module:Protect')
 local protectedFunc = protect(func, errFormat, options)
Arguments edit source
- Template:Code
- Function to be transformed.
 
 - Template:Code (default: Template:Code)
- Custom error message.
 - Use Template:Code to include the message from a caught error.
 
 - Template:Code – optional table with the following fields:
- Template:Code (default: false)
- If true, then Template:Code will be used as is, otherwise it will be wrapped inside a tag 
<strong class="error">. 
 - If true, then Template:Code will be used as is, otherwise it will be wrapped inside a tag 
 - Template:Code (default: true)
- If true, removes location information from caught error messages.
 
 
 - Template:Code (default: false)
 
Return value edit source
The resulting Template:Code is a function, which calls the original function Template:Code, passing all arguments to it, and returns all its return values. If Template:Code throws an error, the specified error message is returned instead.
Example edit source
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: Error: missing argument