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§23.14. Writing, reading and appending text to files
Text can also be saved to a file, and again all file-handling is automatic:
write (text) to (external file)
This phrase makes the given text become the entire contents of the named file. Note that files must have been declared, and must be referred to by their Inform names, not by textual filenames. Example:
append (text) to (external file)
This phrase adds the given text to the end of the current contents of the named file (creating it if it does not exist on disc). Note that files must have been declared, and must be referred to by their Inform names, not by textual filenames. E ample:
The quoted text can, of course, contain substitutions, so can be long and complex if need be.
Text from a file is printed back with the text substitution:
say "[text of (external file)]"
This text expands to the contents of the named file. Note that files must have been declared, and must be referred to by their Inform names, not by textual filenames. Example:
To copy one file to another, for instance,
write "[text of the file of Abecedary Wisdom]" to the file of Secondary Wisdom;
|Start of Chapter 23: Figures, Sounds and Files|
|Back to §23.13. Writing and reading tables to external files|
|Onward to §23.15. Exchanging files with other programs|
The Fourth Body
Some mystery games supply the player with an in-game system for taking notes, in case he doesn't want to rely on scraps of paper next to the computer. One way of doing this is to write out all the player's notes and observations into a notebook file, whose contents can be retrieved during play (or, indeed, after it).
We'll first invent a general system for writing text into notebooks, by creating a new kind called jotter. Each individual jotter will have its own disc file, and there will be basically three things which can be done with jotters: erasing, reading and writing.
The currently erased jotter is an object that varies.
To erase (pad - a jotter):
now the currently erased jotter is the pad;
write "[heading of the currently erased jotter][paragraph break]" to the text file of the pad;
now the pad is fresh.
This is all as might be expected, except perhaps for the business of the "currently erased jotter". Why copy "pad" into this - why not simply write "[heading of the pad]"? The answer is that "pad" is a temporary "let" value, and cannot be used inside other phrases, such as the "write ... to ..." phrase.
We want to erase any jotters when play begins, as otherwise text left over from any previous games will still be visible:
Now we need to create rules to allow the player to control reading, writing and erasing. Reading we will handle with the ordinary examining action, but we create new actions for writing and erasing. A nice little trick allows WRITE WHATEVER to default to writing WHATEVER in a notebook being carried.
Understand "write [text] in [something preferably held]" as writing it in. Understand "write [text]" as writing it in. Writing it in is an action applying to a topic and one thing. Rule for supplying a missing second noun while writing: if a jotter (called the pad) is carried, now the second noun is the pad; otherwise say "You will have to specify what to write that it."
That completes a general-purpose implementation of jotters, and we put it to use:
The player carries a jotter called your notebook. The file of Player's Observations is called "notebook". The text file of your notebook is the file of Player's Observations. The heading of your notebook is "Observations in the Pottingham Green Case".
The Damp Hillside is a room. "It is just after dawn: among the trees there is misty and pale blue light. [if Havers is in the location]The only saturated color in view is the orange-and-yellow jacket of [Detective Havers]. She is trying unsuccessfully to light a cigarette. [end if][paragraph break]The body itself is further down, closer to the bottom of the ravine. It would be foolish to speculate before seeing it, but the odds are that the corpse was rolled down after death. The ground is not steep enough for the fall itself to be deadly."
Detective Havers is a woman in the Damp Hillside. The description is "She gives you a weak smile when you look at her: you know she hasn't slept more than three hours any of the last few nights." Havers is scenery.
Havers is carrying a jotter called Barbara's notebook. The file of Barbara's Observations is called "barbara". The text file of Barbara's notebook is the file of Barbara's Observations. The heading of Barbara's notebook is "I could murder a cup of tea".
Instead of examining your notebook when your notebook is fresh:
say "Your notebook is blank. Back in the office, of course, there are a stack of others. But you brought a fresh notebook in a kind of weary hope. You're going to pretend, just for now, that this body might be unrelated to the graphic string of murders you're already investigating."
The Fifth Body
The implementation here is much like that of the previous example, except that we allow the player to write his notebook input as a separate command, leading to an exchange such as
The opening is much as before:
Now what happens is that the player, having typed WRITE IN NOTEBOOK, will be faced with a ">>" prompt instead of the usual ">": a sign that the input mode has changed.
The next code is to react to reading a command. Whatever the player types at the >> prompt when the target jotter is set will now be recorded in the notebook, though with a character limit of about 60-100 characters depending on how much upper-case and punctuation he uses. (There are ways to lift the character length restriction as well, but they would take us into deeper waters.)
After reading a command when target jotter is a jotter:
now the command prompt is ">";
write in target jotter;
now target jotter is used;
say "You finish writing and fold your notebook away.";
now the target jotter is nothing;
reject the player's command.
The player carries a jotter called your notebook. The file of Player's Observations is called "notebook". The text file of your notebook is the file of Player's Observations. The heading of your notebook is "Sunday Morning".
The Vestry is a room. "[Havers] hangs back by the door: the forensics expert is not finished with a preliminary examination of the body. From here you can't see much, except that the expert has peeled back and laid to one side a liturgical vestment that someone at the church used to cover the corpse until the police came. What was once a cream silk with festive Easter embroidery is now stained with blood-colored handprints."
Havers is carrying a jotter called Barbara's notebook. The file of Barbara's Observations is called "barbara". The text file of Barbara's notebook is the file of Barbara's Observations. The heading of Barbara's notebook is "Sun. AM".