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Enumerating Haiku🔗 i

Programs written in the haiku-enum language define an enumeration of Haiku use the same concrete syntax as for Scribble (described in @ Syntax), except starting in normal racket mode instead of starting in text mode.

The haiku generated by a program in haiku-enum follow the rules and the vocabulary specified in the program. Rules are defined in two parts: a use of starters that indicates how the haiku begin and then a series of uses of rule that determine how the haiku continue (and end).

The vocabulary is specified at the end of the file, using the parts of speech introduced by the rules.

For example, consider this simple program in haiku-enum that has a set of rules that generate some especially boring Haiku:

#lang haiku-enum

(starters

(adjectivenoun))

(rule noun->

verb)

(rule verb->

#:commaadjective)

(rule adjective->

noun)

@adjective[1]{blackfiercegrayplumpwet}

@adjective[2]{achyagiledormantmangysoberwrinkled}

@noun[1]{antowlstagwasp}

@noun[2]{ducklingpandasongbirdswordfish}

@verb[1]{achesbarksclawsclimbsrovessnarlsweeps}

@verb[2]{awaitsbeckonsgallopsgambolsslobbers}

The starters part of the program declares that the Haiku must all begin with an adjective and then transition to the noun state (multiple possible starting parts of speech are allowed; just parenthesize each possibility).

The rules describe the valid states. When in the noun state, the language will generate a noun and then transition to the verb state, as declared just below the starters section in the first rule . Similarly, a verb must be followed by a comma and then an adjective, and the cycle continues.

After all of the rules, the vocabulary is declared. Each vocabulary declaration consists of the number of syllables, followed by words that are in that category of the part of speech and have that many syllables. Use one declaration for each different number of syllables that words in the part of speech may have.

This file then provides:

random-haiku: a function that accepts no arguments and returns a random haiku (as a string),
how-many-haiku:, a natural number that indicates how many different haiku this program generates,
nth-haiku: a function that accepts a natural number less than how-many-haiku and returns the corresponding haiku, and
enum/e: a one-way enumeration of the same haiku that nth-haiku returns
structured-haiku/e: a two-way enumeration that maps the naturals to an sexpression representing the choices made to construct a particular haiku

Examples:

> (display (nth-haiku0))

black stag aches, black stag

aches, black stag aches, black stag aches,

black stag aches, black stag
> (display (nth-haiku(- how-many-haiku1)))

wrinkled duckling weeps,

wrinkled duckling slobbers, fierce

duckling slobbers, fierce
> (display (nth-haiku(quotient (- how-many-haiku1)2)))

plump duckling climbs, wet

ant claws, fierce ant roves, gray stag

barks, plump ant snarls, plump

The library also contains the file "haiku.rkt", a more elaborate example that contains haiku such as these:

> (display (nth-haiku145095608713658901635917363016718021515))

snow gnomes hide, dishrag

coughs, rough blind dog falls, soft moons

fight, sting lithe knives drown
> (display (nth-haiku5842574289046493184639147839447824095))

snow men crawl, bleak lame

earth scolds, fiends dabble, hog shrieks,

sad cow flops, shapeless

The "haiku.rkt" program is a reimplementation of the program that generates random haiku from http://www.everypoet.com/haiku/.

syntax
( rule haiku-state-idword-class-id->next-state...)
(rule haiku-state-id->next-state...)

next-state = maybe-lastnessmaybe-commahaiku-state-id

maybe-lastness =
| #:only-last
| #:not-last

maybe-comma =
| #:comma

Defines a state for haiku named haiku-state-id that, when entered, generates a word from word-class-id and then transitions to one of the states listed in next-state. If word-class-id does not appear, then haiku-state-id is taken as both the name of the state and the name of the class of words to generate.

If #:only-last appears, then this state is entered only when it would be the last word in the haiku. If #:not-last appears, then this state is entered only when it would not be the last word in the haiku.

If #:comma appears, then a comma is generated in the haiku before continuing into the next state.

In addition to defining a new rule, a use of rule defines word-class-id (if the first case is used) or haiku-state-id (if the second case is used). It is defined to accept a natural number and a sequence of strings that are assumed to be words that all have the given number of syllables. The name can be used multiple times with different numbers of syllables.

For example, the rule

(rule adjective->noun)

generates a rule that transitions from the adjective state to the noun state and admits the possibility of defining adjectives by using adjective, e.g.,

(adjective1"tall""fast")
(adjective2"three-point""driven")
(adjective3"athletic")

Use underscores in the word if it should be rendered with a space but count as a single item in a haiku (i.e., it should either appear entirely or not at all), e.g.:

(noun4"Michael_Jordan")

which appears as "Michael Jordan" but never "Michael" or "Jordan" on their own.

syntax
( starters (word-class-idhaiku-state-id)...)

Starts a haiku.

Each clause indicates one way that a haiku can start, namely by generating a word from word-class-id and then moving into the state haiku-state-id.

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