LDraw.org Parts numbering scheme for parts with unknown numbers

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Maintained by: The LDraw.org Standards Committee
Author: The LDraw.org Standards Committee
Writers: Travis Cobbs, Michael Heidemann, Santeri Piippo, Allen Smith, Scott Wardlaw
Contributors: Many

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If a part number is unknown the part in question gets a file name with
uNNNN.dat format, these filenames thus ranging from u1.dat to u9999.dat.
The part remains having the u-prefixed number as long as the part's true
number is unknown.
This unknown number has to be the same as used by Peeron (for example
Peeron: x8888 -> LDraw: u8888)

If Peeron does not list that part a number ranging from u9000.dat to
u9999.dat is to be used.
The numbering for this will be chosen by the Parts Tracker admin like
before with the range of xNNN.dat files.

Peeron should then take our number and make it a x9000.dat - x9999.dat
number.
This way both Peeron and LDraw need only one renumbering should the correct
number get to be known.

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Note: This document is an offical LSC specification and/or language extension. Material changes can only be made after ratification by the LSC. Ratified 2010-02-05

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