Questions tagged [let]
In Lisp-like and functional languages, introduces a list of local variables, each (possibly optionally) with its initial value.
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How to make `set!` change the variable in `let` (Scheme)?
Recently when I self-learnt MIT 6.5151 course, I have read SICP 1 to 2.1 as ps0 requires (also read 2.2.1 as CS 61A notes requires) and then Software Design for Flexibility (SDF) Prologue, chapter 1 ...
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SAS creating global macro and printing it
I am new to SAS environment. I just want to create a global this month variable and print it & use it
in the where condition of data step. My test codes are below:
%macro vars();
%...
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angular 18 - @let syntax in templates
The Angular team just implemented the new @let syntax in templates. According to this comment it's implemented in this commit, which should already be released in version 18.0.2
I updated my NX ...
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Is there an R function that minimise a bivariate function f
I need to write a code that using the R function constrOptim, minimise an bivariate function. Please tell me what is wrong in the constrOptim , went i run the code i have this warning message
"...
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SwiftUI view running twice
I have a view that draws some lines and filled circles. But to know the position of these lines I need to dynamically calculate them as they are being drawn.
I have two issues.
The first is that for ...
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How to fix SwiftUI: Initializer for conditional binding must have Optional type, not 'ChatMessage' [duplicate]
I am a beginner in SwiftUI and I am trying to create a chat app with firestore. I have this issue and I looked many articles but I can't fix it. I'd be very happy if you help me! Thank you!
My Code:
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Why does declaring a variable without a keyword result in a SyntaxError for var and const, but not for let in JavaScript? [duplicate]
Declaring variable in JS without keyword.
I get SyntaxError when I declare variable like var = 1 or const = 1. But I don't get this error when i declare like let = 1. Why is this happening?
var = ...
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Performance increase using `let`?
Compare the following two snippets:
expensiveFunction :: [Integer] -> [Integer -> Bool]
expensiveFunction [] = [const False]
expensiveFunction (x:xs) =
let temp = expensiveFunction xs
in [...
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How to find out how many of each 2, 3 and 4 required to fit in 100 using excel?
I want to determine the numbers or counts of each 2, 3, and 4 required to fit in 100.
I got the formula in Excel which can only return the numbers for two given variables i.e. 2, 3. I want to try for ...
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How to programmatically expand the let* family of functions in racket
Context
This question is tangentially related to a homework assignment, but I am not looking to have someone do my work for me.
I have an assignment where we are discouraged from overuse of let, let*, ...
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Trying to get names from a box on the right to automatically appear in another box when a different box has a value in it
hope the title wasn't too confusing.
this is my project:
I'm trying to figure out how to get the names on the right (NICK-GL) to stack on top of each other at the bottom, when one of the mon-fri ...
user23626448
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Set variables declared through let* as ignorable
I am trying to write a macro that would generate code that looks like:
(defun test ()
(let* ((_ (exp1))
(_ (exp2))
...
(_ (expn)))))
The (expn) calls might be ...
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LET with LOOP construct in Common Lisp
I have the following code:
(let (liste (loop for item from 1 to 20 collect item))
(format t "~{~a~}~" liste))
However portacle complains: The variable FOR is unbound. Why?
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consC in Seasoned Schemer
The seasoned schemer on page 131 and 132 has the below definition of consC and deep.
(define consC
(let ((N 0))
(lambda (x y)
(set! N (add1 N))
(cons z y))))
(define deep
(lambda (...
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Non-state variable inside SwiftUI View
I just rewatched Demistify SwiftUI and noticed that some of the examples use variable properties inside a SwiftUI View, without using the @State property wrapper. For example (around 19.04):
struct ...
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