macros

问题 First I do know about 'import'. When I try 'import' it doesn't work. What I'm trying to do is split a single module into two parts, one of which is editable by a group and the other of which is not. I want the group to write well-defined 'retrieval functions' without the temptation or ability to edit the backend code that runs them (even accidentally). The changes in namespace on an 'import' are getting in my way. I'm looking for a macro-style inclusion of File_A's text within File_B, to be

问题 I would like to write a macro to create shorthand syntax for hiding more verbose lambda expressions, but I'm struggling to understand how to write macros (which I realize is an argument against using them). Given this example: (define alist-example '((x 1 2 3) (y 4 5 6) (z 7 8 9))) (define ($ alist name) (cdr (assoc name alist))) ((lambda (a) (map (lambda (x y z) (+ x y z)) ($ a 'x) ($ a 'y) ($ a 'z))) alist-example) ((lambda (a) (map (lambda (y) (/ y (apply max ($ a 'y)))) ($ a 'y))) alist

问题 I would like to write a macro to create shorthand syntax for hiding more verbose lambda expressions, but I'm struggling to understand how to write macros (which I realize is an argument against using them). Given this example: (define alist-example '((x 1 2 3) (y 4 5 6) (z 7 8 9))) (define ($ alist name) (cdr (assoc name alist))) ((lambda (a) (map (lambda (x y z) (+ x y z)) ($ a 'x) ($ a 'y) ($ a 'z))) alist-example) ((lambda (a) (map (lambda (y) (/ y (apply max ($ a 'y)))) ($ a 'y))) alist

问题 It seems I often spend way too much time trying to get a #define macro to do exactly what i want. I'll post my current dilemma below and any help is appreciated. But really the bigger question is whether there is any utility someone could recommend, to quickly display what a macro is actually doing? It seems like even the slow trial and error process would go much faster if I could see what is wrong. Currently, I'm dynamically loading a long list of functions from a DLL I made. The way I've

问题 I'd like to run a macro on every line in a selection, rather than totalling up the number of lines in my head. For instance, I might write a macro to transform: Last, First Into First Last and I'd like it to run on all these lines: Stewart, John Pumpkin, Freddy Mai, Stefan ... Any ideas Vim gurus? EDIT: This is just an example, obviously this is trivialy regexable, but there are other instances that come up that aren't quite so easy that I'd prefer to use macros. 回答1: Suppose you had a macro

问题 This is continuation of my previous question Missing argument in syntax-rules Hygienic macro call from Scheme R5RS example so you can have only this two cases: First (foo bar baz) ... that can be used as foo ... ==> (foo_1 _ foo_2 _ foo_3 _) bar ... ==> (_ bar_1 _ bar_2 _ bar_3 _) or (foo bar bar) ... but what should expand this expression into? (foo baz) ... Second (foo bar baz ...) which can be used as baz ... that expands into ,@(1 2 3) if input is (anything 0 1 2 3) . Are there any other

问题 I work with large html files that I would like to fragment into separate files. The process of doing this is quite tedious as it requires copying the code, creating a new file, pasting it in the new file, and then selecting a folder and a new name to save it under. Is there a built-in shortcut, macro or extension for VS Code for making this easier? 回答1: Here is a macro which does what you want. I am using the macro extension multi-command but there are others. In settings.json: "multiCommand

问题 Isn't __FUNCTION__ a string literal? I'd always thought it was - along the lines of __FILE__ , but I just discovered I can't adjacently concatenate a string literal to it. If it's not a string literal, what is it defined as? I can't get cscope to resolve it. E.g. #include <iostream> int main( int argc, char* argv[] ) { std::cout << __FILE__ << std::endl; std::cout << __FILE__ "A" << std::endl; std::cout << __FUNCTION__ << std::endl; //std::cout << __FUNCTION__ "A" << std::endl; // Doesn't

问题 I want to know how the "isupper" macro is defined in C/C++. Could you please provide me the same or point me to available resources. I tried looking at ctype.h but couldnt figure it out. 回答1: It's implementation defined -- every vendor can, and usually does, do it differently. The most common usually involves a "traits" table - an array with one element for each character, the value of that element being a collection of flags indicates details about the character. An example would be: traits[

问题 I want to know how the "isupper" macro is defined in C/C++. Could you please provide me the same or point me to available resources. I tried looking at ctype.h but couldnt figure it out. 回答1: It's implementation defined -- every vendor can, and usually does, do it differently. The most common usually involves a "traits" table - an array with one element for each character, the value of that element being a collection of flags indicates details about the character. An example would be: traits[