L2/12-387

Title: Proposed BD11

Source: Andrew Glass

Date: Nov 8, 2012

BD11. Paired punctuation marks are pairs of characters A and B where the following conditions are true:

• A has general category Open_Punctuation (gc = Ps).
• B has general category Close_Punctuation (gc = Pe).
• A and B form a mirrored pair (Bidi_Mirroring_Glyph of A is B).
• A precedes B in the run in logical order.
• A and B occur at the same explicit level without an intervening drop below their level.
• A and B will be in the same isolating run sequence.
• If the number of A characters does not equal the number of B characters, pairs will form with the minimum distances between A and B.

When two pairs of different types of paired punctuation marks overlap, only the first pair in logical order will be considered to be valid paired punctuation marks.

Examples of showing valid and invalid paired punctuation marks

Text Pairings

1 2 3 4 5 6 7 8 9

a ( b ) c 2-4

a ) b ( c None

a ( b ] c None

a ( b { c } d ) e 2-8, 4-6

a ( b ) c ( d ) e 2-4, 6-8

a ( b ) c ) d 2-4

a ( b [ c ) d ] e 2-6

a ( b ] c ) d 2-6

a ( b ( c ) d 4-6