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c++unicodeicu

Checking if a unicode quotation mark is opening or closing

I am writing a lexer that needs to find the boundaries of strings. These strings may be quoted using Unicode characters (i.e. left “ and right ” double quotation marks) that can differentiate things such as strings-within-strings.

To test Unicode character properties I am using the ICU4C library.

I currently test for quotation marks using u_hasBinaryProperty(cp, UCHAR_QUOTATION_MARK).

This works well for finding the quotation marks themselves, but falls short in being able to tell an open-quote from a close-quote.

Is there some property value I can test or other functionality I can use to test the orientation of the quote mark without explicitly testing it against each possible type of quote?

Solution

  • Whether a quotation mark is opening or closing is language/locale dependent and therefore out of scope for Unicode. Unicode deals with scripts only. Examples:

    • «Swiss»
    • »Polish«
    • »Finnish»

    Look elsewhere.