2021-02-01 18:39:00 +01:00
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/*
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2022-08-02 08:19:38 +02:00
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Package uniseg implements Unicode Text Segmentation and Unicode Line Breaking.
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Unicode Text Segmentation conforms to Unicode Standard Annex #29
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(https://unicode.org/reports/tr29/) and Unicode Line Breaking conforms to
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Unicode Standard Annex #14 (https://unicode.org/reports/tr14/).
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In short, using this package, you can split a string into grapheme clusters
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(what people would usually refer to as a "character"), into words, and into
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sentences. Or, in its simplest case, this package allows you to count the number
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of characters in a string, especially when it contains complex characters such
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as emojis, combining characters, or characters from Asian, Arabic, Hebrew, or
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other languages. Additionally, you can use it to implement line breaking (or
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"word wrapping"), that is, to determine where text can be broken over to the
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next line when the width of the line is not big enough to fit the entire text.
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Grapheme Clusters
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Consider the rainbow flag emoji: 🏳️🌈. On most modern systems, it appears as one
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character. But its string representation actually has 14 bytes, so counting
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bytes (or using len("🏳️🌈")) will not work as expected. Counting runes won't,
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either: The flag has 4 Unicode code points, thus 4 runes. The stdlib function
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utf8.RuneCountInString("🏳️🌈") and len([]rune("🏳️🌈")) will both return 4.
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The uniseg.GraphemeClusterCount(str) function will return 1 for the rainbow flag
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emoji. The Graphemes class and a variety of functions in this package will allow
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you to split strings into its grapheme clusters.
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Word Boundaries
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Word boundaries are used in a number of different contexts. The most familiar
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ones are selection (double-click mouse selection), cursor movement ("move to
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next word" control-arrow keys), and the dialog option "Whole Word Search" for
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search and replace. This package provides methods for determining word
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boundaries.
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Sentence Boundaries
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Sentence boundaries are often used for triple-click or some other method of
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selecting or iterating through blocks of text that are larger than single words.
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They are also used to determine whether words occur within the same sentence in
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database queries. This package provides methods for determining sentence
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boundaries.
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Line Breaking
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Line breaking, also known as word wrapping, is the process of breaking a section
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of text into lines such that it will fit in the available width of a page,
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window or other display area. This package provides methods to determine the
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positions in a string where a line must be broken, may be broken, or must not be
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broken.
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2021-02-01 18:39:00 +01:00
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*/
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package uniseg
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