Pages

Example 303

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A book with pages that can be read by number (as in "read page 3 in…") and which accepts relative page references as well (such as "read the last page of…", "read the next page", and so on).

Suppose we have a book that the player must consult page-by-page, and we want to be able to accept all of the following input:

> READ BOOK (to choose a random page and read it)
> READ PAGE 1 IN BOOK
> READ PAGE 2
> READ THE LAST PAGE OF THE BOOK
> READ THE NEXT PAGE
> READ PREVIOUS PAGE IN BOOK
> READ THE FIRST PAGE

One approach would be to write many different understand rules and actions: one action for reading randomly, one for reading a specific page, one for reading the first page, one for reading the previous page, one for reading the next page, and one for reading the last page. But this gets tedious to construct and maintain.

More usefully, we could consider that all of the last four options are essentially the same action at heart: the player is asking to read a page in the book using a name rather than a number, and we will have to perform a minor calculation to discover what the number should be. Here's an implementation using named values to resolve this problem:

Play/modify in Borogove

Play in Quixe

"Pages"

The Library is a room. The sinister book is carried by the player. The sinister book has a number called the last page read. The sinister book has a number called the length. The length of the sinister book is 50.

Understand the command "read" as something new.

Understand "read [something]" or "consult [something]" or "read in/from [something]" as reading. Reading is an action applying to one thing, requiring light.

Understand "read [number] in/from/of [something]" or "read page [number] in/from/of [something]" or "look up page [number] in/from/of [something]" or "consult page [number] in/from/of [something]" as reading it in. Reading it in is an action applying to one number and one thing, requiring light.

Named page is a kind of value. The named pages are first page, last page, next page, previous page.

To decide what number is the effective value of (L - last page):

decide on the length of the book.

To decide what number is the effective value of (F - first page):

decide on 1.

To decide what number is the effective value of (N - next page):

let X be the last page read of the book plus 1;

decide on X.

To decide what number is the effective value of (P - previous page):

let X be the last page read of the book minus 1;

decide on X.

Understand "read [named page] in/from/of [something]" or "read the [named page] in/from/of [something]" as reading it relatively in. Reading it relatively in is an action applying to one named page and one thing, requiring light.

Does the player mean reading something in the sinister book: it is very likely.

This is the book requirement rule:

if the player is not carrying the sinister book, say "You're not reading anything." instead.

Check reading it relatively in:

if the second noun is not the sinister book, say "There are no pages in [the second noun]." instead;

abide by the book requirement rule.

Carry out reading it relatively in:

let N be the effective value of the named page understood;

now the number understood is N;

try reading N in the book.

Check reading it in:

if the second noun is not the sinister book, say "There are no pages in [the second noun]." instead;

abide by the book requirement rule.

Check reading it in:

if the number understood is greater than the length of the sinister book, say "There are only [length of sinister book in words] pages in the book." instead;

if the number understood is less than 1, say "The page numbering begins with 1." instead.

Carry out reading it in:

read page number understood.

Check reading:

if the noun is not the sinister book, say "There are no pages in [the noun]." instead;

abide by the book requirement rule.

Carry out reading:

let N be a random number between 1 and the length of the sinister book; now the number understood is N;

say "You flip the pages randomly and arrive at page [the number understood]:[paragraph break]";

try reading the number understood in the sinister book.

Table of Book Contents

page	content
2	"dhuma jyotih salila marutam / samnipatah kva meghah / samdes arthah kva patukaranaih / pranibhih prapaniyah"
13	"amathesteron pws eipe kai saphesteron"
50	"Rrgshilz maplot..."

To read page (N - a number):

now the last page read of the sinister book is N;

if there is a content corresponding to a page of N in the Table of Book Contents:

choose row with a page of N in the Table of Book Contents;

say "You read: '[content entry]'[paragraph break]";

otherwise:

say "Page [N] appears to be blank."

To read page (N - 47):

say "Your eyes burn; your ears ring. Beneath your gaze, the dreadful sigils writhe, reminding you of that which lies outside the edges of the universe...";

end the story saying "You have lost your remaining sanity".

Test me with "read from the sinister book / read the book / read the next page / read page 2 / read previous page / g / read the first page / read the last page of the book / read the next page / read 47 in book".

Library

>(Testing.)

>[1] read from the sinister book
You flip the pages randomly and arrive at page 34:

Page 34 appears to be blank.

>[2] read the book
You flip the pages randomly and arrive at page 22:

Page 22 appears to be blank.

>[3] read the next page
(in the sinister book)
Page 23 appears to be blank.

>[4] read page 2
(in the sinister book)
You read: "dhuma jyotih salila marutam / samnipatah kva meghah / samdes arthah kva patukaranaih / pranibhih prapaniyah"

>[5] read previous page
(in the sinister book)
Page 1 appears to be blank.

>[6] g
(in the sinister book)
The page numbering begins with 1.

>[7] read the first page
(in the sinister book)
Page 1 appears to be blank.

>[8] read the last page of the book
You read: "Rrgshilz maplot..."

>[9] read the next page
(in the sinister book)
There are only fifty pages in the book.

>[10] read 47 in book
Your eyes burn; your ears ring. Beneath your gaze, the dreadful sigils writhe, reminding you of that which lies outside the edges of the universe...

*** You have lost your remaining sanity ***