Word ladder¶
word_ladder · word · validated
A chain of words in which each step changes exactly one letter of the word before it, every step being itself a word.
Provenance¶
- Source: Lewis Carroll, Doublets, a Word Puzzle (1879)
- Attribution:
primary— a named author, work and year this catalogue stands behind - Checkability:
self— decidable from the text and its parameters alone - Attested:
author-stated— the originator set this rule down
Details¶
- Kind: both
- Languages: en, de, fr
- Requires:
tokens,alphabet,fold_diacritics,lexicon.words - Deterministic: yes
- Also known as: doublets, word golf
- In other languages: Wortleiter (de), Échelle de mots (fr)
Notes¶
German and French are declared, and the checker takes a fold_diacritics parameter so both declarations hold. Folded — the house default — schon and schön are the same word and the step is rightly refused; unfolded, they differ in exactly one letter and the canonical German doublet is accepted. French raises the identical question with cote/côte and sur/sûr, and the same parameter answers it the same way. The generator substitutes over alphabet() widened by vowels(), which is how it reaches ä, ö and ü at all; ß is in neither, so apply cannot produce Maße from Masse although check accepts that step unfolded.
Prompt hint¶
Move from the first word to the last, changing one letter at a time, each step a real word.
Parameters¶
| Name | Type | Default | Description |
|---|---|---|---|
fold_diacritics |
boolean | True |
Treat accented letters as their base letter, and ß as ss. |
target |
— | None |
The word apply searches a ladder toward. |
Examples¶
cold-to-warm¶
en — this text satisfies the procedure.
cold cord card ward warm
Source: Lewis Carroll's own example ladder, Doublets, a Word Puzzle (1879)
two-letters-in-one-step¶
en — this text does not satisfy the procedure.
cold card warm
Source: constructed counterexample; card to warm changes two letters at once
wald-zu-halt¶
de — this text satisfies the procedure.
wald bald ball fall hall halt
Source: constructed example; the game itself is Carroll's, "Wortleiter" its established German name (already in this row's names)
zwei-buchstaben-in-einem-schritt¶
de — this text does not satisfy the procedure.
wald ball halt
Source: constructed counterexample; wald to ball changes two letters at once
schon-zu-schoen-ungefaltet¶
de — this text satisfies the procedure.
schon schön
Parameters: fold_diacritics=False
Source: constructed example; the canonical German doublet, which only exists with folding off
schon-zu-schoen-gefaltet¶
de — this text does not satisfy the procedure.
schon schön
Source: constructed counterexample; folded, the two are the same word and no step happened
chat-a-chez¶
fr — this text satisfies the procedure.
chat char cher chez
Source: constructed example; each step changes one letter and every rung is a word the lexicon knows
deux-lettres-en-un-pas¶
fr — this text does not satisfy the procedure.
chat cher chez
Source: constructed counterexample; chat to cher changes two letters at once