My LOLCODE suggests a few new things:

<code>
HAI
CAN HAS STDIO?

VISIBLE "Welcome to the basic calculator."
I HAS A NUMBER1 IZ 0
I HAS A NUMBER2 IZ 0
I HAS A OPERATION IZ NOTHING
I HAS A LINE IZ NOTHING
I HAS A COMPLETE IZ NOTWORKZ0RZ
I HAS A RESULT IZ 0

VISIBLE SAME LINEZ "Try what: "
TXT ME A LINE

IZ MAGICZ ON LINE WITH /(\n) (.?) (\n)/ ACTUALLY WORKZ0RZ?
        NUMBER1 IZ MAGICZ1
        OPERATION IZ MAGICZ2
        NUMBER2 IZ MAGICZ3
        COMPLETE IZ WORKZ0RZ
        KTHXBYE
:(
        VISIBLE "Can not parse line."
        COMPLETE IZ NOT WORKZ0RZ
        KTHXBYE

IZ COMPLETE WORKZ0RZ?
        WTF IZ OPERATION?
                OMG +
                        RESULT IZ UP NUMBER1!!NUMBER2
                OMG -
                        RESULT IZ DOWN NUMBER1!!NUMBER2
                OMG *
                        RESULT IZ TIMEZ NUMBER1!!NUMBER2
                OMG /
                        RESULT IZ DIVIDEZ NUMBER1!!NUMBER2
        KTHXBYE
:(
        VISIBLE "Didn't work :("
        DIAF! 2 "This is dieing"

VISIBLE "Result is: " ANDZ RESULT ANDZ "."

KTHXBYE
</code>

**VISIBLE SAME LINEZ**: Not inserting a newline, like default VISIBLE seems to do.

**MAGICZ ON <variable> WITH <regexp>**: Run regexps on the variable.  Return true/false.  With () groupings, use MAGICZ1, MAGICZ2, MAGICZ3, MAGICZ4, etc.

**ACTUALLY**: In a condition, test to see if something (iz) equal.

**WORKZ0RZ/NOT WORKZ0RZ**: TRUE/FALSE, possibly NOTWORKZ0RZ instead of two words.

**TIMEZ/DIVIDEZ**: TIMEZ was used elsewhere, DIVIDEZ I just added.

**DIAF**: Die (in a fire).  Exit.  First (optional) variable is the exit code.  Second (optional) variable is the message.

**ANDZ**: Append a variable into a string.

----
The OMG/WTF case statement is a thing of beauty. Maybe use WTFBBQ as the default (no case matched?)  --- //Church Tucker, 2007/05/30 16:56//