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+--- Forum: HP Prime (/forum-5.html)
+--- Thread: self modifying code (/thread-12737.html)
self modifying code - Wes Loewer - 04-04-2019 06:40 PM
It occurred to me today that self modifying code is easily done in PPL. Save the following program as HiBye and run it a few times from Home.
Code:
EXPORT HiBye()
BEGIN
LOCAL source;
source:=Programs("HiBye");
IF INSTRING(source,"He"+"llo") THEN
source:=REPLACE(source,"He"+"llo","Good"+"bye");
ELSE
source:=REPLACE(source,"Good"+"bye","He"+"llo");
END;
Programs("HiBye"):=source;
RETURN "Hello";
END;hee hee.
RE: self modifying code - Carlos295pz - 04-04-2019 10:43 PM
Editing programs with Programs("name") is wonderful until you hit the limit of 65,535 characters for the string type.
RE: self modifying code - Wes Loewer - 04-05-2019 12:14 PM
With Programs():=string, is the program compiled at save time or upon first run time?
RE: self modifying code - Carlos295pz - 04-05-2019 01:02 PM
Programs():=string compiles during execution, that is why you can even abort the execution if you find a difference relevant to the previous code. This instruction it returns 1 if compiled correctly and 0 if there are syntax errors.