|Chapter 6: Commands|
|6.18. Alternatives To Standard Parsing|
Very occasionally, for out-of-the-ordinary games, we want to make major changes to the way that Inform ordinarily understands commands.
Cloves shows how we might read adverbs in the player's command: adverbs are challenging because they can legitimately appear anywhere in a command structure, so must be found and accounted for before the rest of the command is understood.
Fragment of a Greek Tragedy goes further, substituting a keyword-recognition parser for the usual structure of commands and objects.
Less drastically, menus of numbered options can temporarily replace or augment standard commands. Down in Oodville demonstrates how to add a list of transporter destinations from which the player may choose by numeral.
See Traits Determined By the Player for ways to ask the player a question at the beginning of play
See Saying Simple Things for a way to ask the player a yes-no question any time during play
| Example Cloves|
Accepting adverbs anywhere in a command, registering what the player typed but then cutting them out before interpreting the command.
| Example Fragment of a Greek Tragedy|
Responding to the player's input based on keywords only, and overriding the original parser entirely.
| Example Down in Oodville|
Offering the player a choice of numbered options at certain times, without otherwise interfering with his ability to give regular commands.