![]() ![]() and this is the action from the earlier lisp exampleĭo (setq ,result (append ,result (list ,expression)))) conditional-test is (= (mod x 2) 0) in our examples list is the list literal we are suppose to iterate over store nil in the unique variable name generated above the arguments are really code so we can substitute them create a unique variable name for the result Its syntax will be exactly like the python that we used in the example - (lcomp x for x in (range 10) if (= (% x 2) 0)) (defmacro lcomp (expression for var in list conditional conditional-test) So we can define a macro called lcomp (short for list comprehension). The second part is the Lisp reader which intelligently substitutes macros for code but that is best illustrated below: This list notation is part of the magic that goes into macros. You can think of `(1 2 ,x) as the equivalent of Python's where x is a variable previously defined. You can assign it to another variable or use it in place. The literal '(1 2 3) is the equivalent of Python's. Escapes are indicated by the comma operator. The quasiquote or backtick ( `) indicates the next token is a literal with escapes. The quote ( ') indicates the next token is a literal. Lisp defines a couple of special syntax forms. In fact, we're using one macro already (the loop macro). So we could define DSL for doing list comprehensions. Of course that's a lot of typing and programmers are lazy. That is, a piece of code, read by the interpreter (or compiler), which takes in code as an argument, manipulates and the returns the result, which is then run in-place. It is a transformation performed on code by code. you can safely ignore them unless you are running this codeĭo (setq divisibleByTwo (append divisibleByTwo (list x))))īefore I go further, I should better explain what a macro is. the following two functions just make equivalent of Python's range function I should note this contrived example is picked to be identical to the Python code not a good example of Lisp code. Let's invoke our suspension of disbelief and pretend Lisp has a very limited loop macro that just does iteration and no easy way to do the equivalent of list comprehensions. Back in the Python 1.5 days there was no such syntax you'd use something more like this: divisibleByTwo = Yields a list containing all even numbers between 0 and 9. This gives a simple syntax for a common case. Here is a more concrete example: Python has list comprehensions built into the language. Now, the DSLs can have syntax similar to Lisp (like Peter Norvig's Prolog Interpreter for Common Lisp) or completely different (e.g. These languages are embedded right into the existing Lisp code. But it would be definitely better when the developers of IDM fix that bug in a future version as soon as possible, best in a hotfix version of UE v21.00 as this is an ugly bug.To give the short answer, macros are used for defining language syntax extensions to Common Lisp or Domain Specific Languages (DSLs). That is definitely a bug of UltraEdit which can be worked around as you have proven. But the Find command after Top always failed if a Find before Top failed too. I could see that command Top was executed after a not successful Find and therefore the caret was blinking at top of the file after the macros finished. That's the reason why command Top or Bottom must be used to move caret to other end of file as you have done here absolutely correct. This behavior is needed to avoid endless loops. The search configuration setting Continue find at End of File is always temporarily disabled as also the replace all option Replace All is from top of file and similar options when running a script/macro. Please note that a Find/ Replace executed from within an UltraEdit macro or script is always only from current position of the caret down to end of file (search downwards) or up to beginning of file (search upwards). So can anyone explain to me what is happening? Thanks in advance. The only way to break out of it is by printing some text (and removing it). ![]() Result: Again the Find command stops functioning. I will select a piece of text (John) in stead of searching for it directly. Result: This works fine, because there are 2 Eds. Result: It will not be able to find the word Ed. ![]() The actual macro I am using is bigger, but I can demonstrate what is happening with a very simple example: What happens is, if I search for a keyword twice and there is only 1 of them in the document, subsequent Find commands will stop to function. I was wondering if I am doing something wrong or if this is a bug. I am a beginner with macros and ran into a problem. ![]()
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