Disembodied list and data retrieve

Hello all,

Sorry if this question has been asked before. I have the following
SKILL function and I noticed that evaluating CMD1 and CMD2 retrieves
different info from list1 and list2. The difference between the two list
is that list1 is formed using '( ) operator while list2 list("....")
function. Appreciate any help from more knowledgeable coder. Thanks.




======================== CUT HERE ====================
procedure(proc1( )

let((list1 list2 cmd1 cmd2 item1 item2)

list1 = '(nil CELL pmos PINNAME g LAYER metal1 PURPOSES drawing)
list2 = list(nil "CELL" "pmos" "PINNAME" "g" "LAYER"
"metal1" "PURPOSES" "drawing")

printf("LIST1: %L\n", list1);
;; prints ----> (nil CELL pmos PINNAME g LAYER metal1
PURPOSES drawing)

printf("LIST2: %L\n", list2);

;; prints ----> (nil "CELL" "pmos" "PINNAME" "g" "LAYER"
"metal1" "PURPOSES" "drawing")


cmd1 = strcat("list1" "->" "LAYER");
item1 = evalstring(cmd1);

cmd2 = strcat("list2" "->" "LAYER");
item2 = evalstring(cmd2);

printf("CMD1= %s ITEM1: %L\n", cmd1 item1);
; prints -----> "metal1" <---- THIS IS DIFFERENT

printf("CMD2= %s ITEM2: %L\n", cmd2 item2);
; prints -----> "nil" <---- THIS IS DIFFERENT
);
);

 

list1 = '(nil CELL pmos PINNAME g LAYER metal1 PURPOSES drawing)

It appears that in disembodied property lists, the name of a property (name/value pair) must be a
symbol, not a string.

So list2 should rather look like

list2 = list(nil 'CELL "pmos" 'PINNAME "g" 'LAYER "metal1" 'PURPOSES "drawing")

This is awkward, for you can simply do

item1 = list1->LAYER

Or, equivalently

item1 = get(list1 'LAYER)
item1 = getq(list1 LAYER)

prop = 'LAYER
item1 = get(list1 prop)

etc..

There's however an important difference between list1 and list2 : list2 will be reinitialized each
time the function is called, while list1 will keep its value. See this post for details
http://groups.google.ch/group/comp.cad.cadence/browse_frm/thread/3161f757fe0532fa/0eda6695ce937c29


Stéphane