problem set complete #2
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ROgbonna1
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ROgbonna1
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This is a really strong submission. Some critical changes to make but they are all pretty much based on one misunderstanding of how var variables are scoped. Make these changes and push them back up this week.
| **1. How do variables declared with `let`, `const`, and `var` differ? Be sure to touch on _scope_, _reassignment_, and _hoisting_ for each.** | ||
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| To begin with, the declaration of all three of these variable types are automatically | ||
| hoisted by javascript right before runtime, simply because they are variables. |
| To begin with, the declaration of all three of these variable types are automatically | ||
| hoisted by javascript right before runtime, simply because they are variables. | ||
| As for their differences, variables declared with `const`, are designed to | ||
| be constant and therefore, JavaScript does not allow it's value to be reassigned. |
| On the other hand, using `let` to declare a variable does allow you to reassign | ||
| its value later on. `let` and `const` are scoped variables, which means that its | ||
| existence can only be detected within its parent scope, whether that be global | ||
| or local. As for `var` its properties are the same as `let`, except for the fact |
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This is incorrect. Variables declared with var have a scope as well. Their scopes are defined by functions. We say they are function scoped.
fellow-submissions/devonte-duncan.md
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| scope as well as in the local scope of the `testScope` function. The value of `a` | ||
| that gets logged on lines 24 and 26 is "outer" because that's the onlt value of `a` | ||
| that it has access to. Meanwhile "undefined" is logged because the function `testScope` | ||
| is referenced, however there is no return value within it, thus "undefined" is logged. |
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What about the local variable a defined within the testScope function? Run this in the console and tell me what you get.
fellow-submissions/devonte-duncan.md
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| console.log(a); | ||
| ``` | ||
| This above code will log: | ||
| "undefined" |
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We don't get undefined because the function hello does not log anything.
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| sayItLoud(); | ||
| ``` | ||
| The variable `name` was declared and initialized within the global scope, and |
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| let greeting = "Hello" | ||
| ``` | ||
| This logs an error, because `let` is a scoped variable, JavaScript cannot access it until |
| console.log(`Status for Problem Set: ${problemSet}`); | ||
| ``` | ||
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| This code logs "Status for Problem Set: undefined". This is because the variable |
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Answer is correct but explanation has a critical flaw. problemSet is not initialized in the body of that function. Remember: function parameters become locally scoped variables in the body of the function. Thus, when we assign the parameter a value in the function, it does not impact the binding of the argument passed to that function.
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| console.log(advice); | ||
| ``` | ||
| The variable `advice` is declared locally within the if statement, therefore when |
| console.log(advice); | ||
| ``` | ||
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| This code works despite the variable `advice` being declared locally because |
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Half correct. Make this change.
Variables declared with var are function scoped, not block scoped. Thus, advice can be accessed outside of the block where it is declared.
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