Error handling (1 Viewer)

sub ImportFile()
on error goto error_handler
	'stuff to check if file exists
	...
	'stuff to open file 
	...
	'stuff to import file
	...
error_handler:
	erm help! I don't know what caused the error!
end sub

sub ImportFile()
	somefile = "c:\myfile.txt"
	If FileExists(somefile) then
		if readfile(somefile) then
			if importfile(somefile) then
			   msgbox "file imported"
			else
				msgbox "error importing file"
			end if
		else
			msgbox "couldn't read file"
		end if
	else
		msgbox "file not found"
	end if
end sub

function FileExists(strfile as file) as boolean
	'code to check if file exists
	if fileexists return true else return false
end function

function readfile(strfile as file) as boolean
	...
end function

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