Spelling Suggestion Mechanisms in Vim

are correct but hardly ever used and could be a misspelled often-used word. - For making suggestions the speed is less important and requiring to install another program or library would be acceptable. But the word lists probably differ, the suggestions may be wrong words. Spelling suggestions *develop-spell-suggestions* For making suggestions there are two basic mechanisms: 1. Try changing the bad word a little bit and check for a match with a good word. Or go through the list of good words, change them a little bit and check for a match with the bad word. The changes are deleting a character, inserting a character, swapping two characters, etc. 2. Perform soundfolding on both the bad word and the good words and then find matches, possibly with a few changes like with the first mechanism. The first is good for finding typing mistakes. After experimenting with hashtables and looking at solutions from other spell checkers the conclusion was that a trie (a kind of tree structure) is ideal for this. Both for reducing memory use and being able to try sensible changes. For example, when inserting a character only characters that lead to good words need to be tried. Other mechanisms (with hashtables) need to try all possible letters at every position in the word. Also, a hashtable has the requirement that word boundaries are identified separately, while a trie does not require this. That makes the mechanism a lot simpler. Soundfolding is useful when someone knows how the words sounds but doesn't know how it is spelled. For example, the word "dictionary" might be written as "daktonerie". The number of changes that the first method would need to try is very big, it's hard to find the good word that way. After soundfolding the words become "tktnr" and "tkxnry", these differ by only two letters. To find words by their soundfolded equivalent (soundalike word) we need a list of all soundfolded words. A few experiments have been done to find out what the best method is. Alternatives: 1. Do the sound folding on the fly when looking for suggestions. This means walking through the trie of good words, soundfolding each word and checking how different it is from the bad word. This is very efficient for memory use, but takes a long time. On

This section delves into the two main mechanisms for providing spelling suggestions in Vim. The first involves trying slight modifications of the misspelled word to match correct words, effective for catching typing errors, and uses a trie data structure for efficiency. The second method uses soundfolding to match words that sound similar but are spelled differently, helpful for phonetic misspellings. It then discusses approaches to find soundalike words.