Revised Why local variables are called "let"

blog-posts/whyLocalVarCallLet.md

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                                            title: Why local variables are called "let"
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
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                                            date: 2022 Jan 10
                                        
                                        
                                            
                                            
                                            
                                            
                                        
                                    
                                
                                
                                
                            
                                
                                    
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                                        updated: 2024 Feb 2
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                        
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                                        <p>In JavaScript there are 3 different kinds of variables, global variables(using <span class="code">var</span>), constants(<span class="code">const</span>, and local variables(<span class="code">let</span>). All of the act allittle differently from eachother. Allow me to explain what they do.</p><p>Global variables, made using <span class="code">var</span>, are as they sound, global variables. Once defined, they can be used, edited, or redefind anywhere.</p><p>Constants, defined with <span class="code">const</span>, are constant, they cannot change, at all.</p><p>Local variables, defined with <span class="code">let</span>, are variables that can only be used in the place that it is defined, like a function, and it's children.</p>Now that we has that established, <em>let</em>'s talk about how local variables got their name.<p>Turns out "let" is a mathematical term. <span class="quote">The <b>"let" expression</b> may also be defined in mathematics, where it associates a Boolean condition with a restricted scope.</span> <a href="https://en.m.wikipedia.org/wiki/Let_expression" class="source">[source]</a>. It was first used in programming in early languages like Basic.</p>In case you're wondering, the main source is <a href="https://stackoverflow.com/a/37917071">this answer on Stack Overflow</a>.
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
                                
                                
                                
                            
                                
                                    
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                                        In JavaScript there are 3 different kinds of variables, global variables(using `var`), constants(`const`, and local variables`let`). All of the act a little differently from each other. Allow me to explain what they do.
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
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                                        Global variables, made using `var`, are as they sound, global variables. Once defined, they can be used, edited, or redefined anywhere.
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
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                                        Constants, defined with `const`, are constant, they cannot change, at all.
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
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                                        Local variables, defined with `let`, are variables that can only be used in the place that it is defined, like a function, and it's children.
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
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                                        Now that we has that established, *let*'s talk about how local variables got their name.
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
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                                        Turns out "let" is a mathematical term.
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
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                                        > The **"let" expression** may also be defined in mathematics, where it associates a Boolean condition with a restricted scope.
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
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                                        > <cite>Quote from [Wikipedia "Let expression"](https://en.wikipedia.org/w/index.php?title=Let_expression&oldid=1187985658) as of <time>2024 Feb 2</time></cite>
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
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                                        It was first used in programming in early languages like Basic.
                                        
                                        
                                        
                                    
                                
                                
                                
                            
                                
                                    
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                                        In case you're wondering, the main source is an answer on Stack Overflow: *"Why was the name 'let' chosen for block-scoped variable declarations in JavaScript?"*, answer by [exebook](https://stackoverflow.com/users/1968972), edited by [Pikamander2](https://stackoverflow.com/users/1741346); [link](https://stackoverflow.com/a/37917071).