According
to ISO TC184/SC4 standards, including ISO 10303 (STEP), entity data
types in EXPRESS schemas have a corresponding "short name" in addition
to their full "long" name. These short names originally grew out of the
concern for keeping files as short as possible, as the long names were
very long and appeared many times in a file. Short names are mainly
used in exchange files, while long names are mainly used in EXPRESS
models.
A directory with short names is defined for each express project.
Its location may be changed by the user, if default location is not
acceptable.
Each express named type may be given an optional short name.
Such short names are supported also by JSDAI.
If the short name directory for the project contains the proper short
name information for a named type,
the corresponding short name is attached to that named type.
The information about short names has to be provided in the following
way:
The short name directory must contain a number of files with extensions
.SN
The names of the files correspond to the names of express schemas,
i.e., some or all express schemas used by the project may
have corresponding files in the short name directory. Also files for
other schemas may be present, they are ignored.
Each short name (.SN) file must contain a comma separated list, a line
per named type,
a long name followed by comma followed by the corresponding short name,
all in capital letters.