I need to list all characters from the categories ID Start and ID Continue in Unicode. Where could I do that for a specific version of Unicode (in this case, Unicode 5)?

I think the site https://codepoints.net doesn't allow doing this for specific Unicode version.


As per Unicode® Standard Annex #31 (Unicode identifier and pattern syntax), ID_Start and ID_Continue character categories are derived from the Unicode General_Category (read whole UnicodeData File Format and Unicode character database articles).

See Table 2. Properties for Lexical Classes for Identifiers (digest of):

  • ID_Start characters are derived from the Unicode General_Category of uppercase letters, lowercase letters, titlecase letters, modifier letters, other letters, letter numbers, plus Other_ID_Start, minus Pattern_Syntax and Pattern_White_Space code points.

    • In set notation:
    • [[:L:][:Nl:][:Other_ID_Start:]--[:Pattern_Syntax:]--[:Pattern_White_Space:]]
  • ID_Continue characters include ID_Start characters, plus characters having the Unicode General_Category of nonspacing marks, spacing combining marks, decimal number, connector punctuation, plus Other_ID_Continue , minus Pattern_Syntax and Pattern_White_Space code points.

    • In set notation:
    • [[:ID_Start:][:Mn:][:Mc:][:Nd:][:Pc:][:Other_ID_Continue:]--[:Pattern_Syntax:]--[:Pattern_White_Space:]]

We can see reference to Other_ID_Start, Other_ID_Continue, Pattern_Syntax and Pattern_White_Space here; for instance:

The exact list of characters covered by the Other_ID_Start and Other_ID_Continue properties depends on the version of Unicode. For more information, see Unicode Standard Annex #44, “Unicode Character Database” [UAX44].

Parse UnicodeData.txt, apply valid regex(es) created from above set notation. Apply to proper version of UnicodeData.txt, browsing from Index of /Public.

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  • Very much thanks thanks, I think with your help I'm able to get the code points for ID_START and ID_CONTINUE, I'll also try to fit it with ECMAScript 4...
    – Klaider
    Apr 1 '17 at 10:16

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