2011

transparently, not requiring the call to the AutoLISP princ function. If the
special character ^P (which switches MENUECHO on and off) is omitted in
both cases, the DIESEL expression displays only the issued command, whereas
the AutoLISP expression displays the entire line of code.
Because the value returned by a DIESEL expression is a text string, it can be
used in response to an AutoLISP getxxx function call. This functionality
enables menu items to evaluate current drawing conditions and to return a
value to an AutoLISP routine.
The next example is based on these assumptions:
■ The AutoLISP routine is loaded into memory.
■ The CUI excerpt is included in the current customization file.
■ The symbols to insert are one unit high by one unit wide.
■ The DIMSCALE variable is set to the drawing's scale factor (that is, a drawing
to be plotted at a scale of 1" = 10' would have a scale factor of 120, or a
1/4" = 1' scale drawing would have a scale factor of 48).
If you load and execute the sample AutoLISP routine, AutoCAD for Mac inserts
the symbol at the size and location you have specified. When plotted, the
symbols are the specified size (if the drawing is plotted at the same scale as
that specified by DIMSCALE).
72 | Chapter 5 DIESEL