L2/03-033

Title: Variation Selector Property
Source: Mark Davis
Date: February 4, 2003

We have the important new type of characters, variation selectors. However,
we do not provide a property to distinguish those characters.

1. I suggest that we define a new property: Variation_Selector, abb: VS

180B..180D    # Mn   [3] MONGOLIAN VARIATION SELECTORs
FE00..FE0F    # Mn  [16] VARIATION SELECTORs
E0100..E01EF # Mn [250] VARIATION SELECTORs

2. Once this is done, we can clean up the definitions of Default Ignorable
Code Point, to the following:

a. Make Other_Default_Ignorable_Code_Point just contain the ranges of
special Cn characters that are not covered by other properties.

Other_Default_Ignorable_Code_Point:

2064..2069    # Cn   [6]
FFF0..FFF8    # Cn   [9]
E0000         # Cn
E0002..E001F  # Cn  [30]
E0080..E0FFF  # Cn [3968]

b. Make the derived property Default_Ignorable_Code_Point as follows. Note:
this would not change the composition of Default_Ignorable_Code_Point other
than the updates needed for 4.0.

<old>
# Derived Property: Default_Ignorable_Code_Point
#  Generated from <2060..206F, FFF0..FFFB, E0000..E0FFF>
#    + Other_Default_Ignorable_Code_Point + (Cf + Cc + Cs - White_Space)
</old>
<new>
# Derived Property: Default_Ignorable_Code_Point
#  Generated from Other_Default_Ignorable_Code_Point + Variation_Selector
#      + Cf + Cc + Cs - White_Space
</new>


One addendum: we decided in the last meeting to add non-characters to DICPs,
so the end result would be;

# Derived Property: Default_Ignorable_Code_Point
#  Generated from Other_Default_Ignorable_Code_Point + Variation_Selector
#      Noncharacter_Code_Point + Cf + Cc + Cs - White_Space