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JAVASCRIPT / CHAPTER 02

JavaScript
Data.

Expense data: arrays, objects, iteration, and a report. Learn and Practice per lesson; challenges are separate.

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JavaScript

13 lessons available

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The foundations behind your ideas.

1. 01

   Arrays · Locked

   array + .length

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2. 02

   Mutate · Locked

   .push + const

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3. 03

   for...of · Locked

   array iteration

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4. 04

   Accumulate · Locked

   sum + average

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5. 05

   Objects · Locked

   category + amount

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6. 06

   Array of Objects · Locked

   list of records

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7. 07

   Callbacks · Locked

   arrow function

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8. 08

   Callback Argument · Locked

   callback as argument

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9. 09

   map · Locked

   amountsOnly + map

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10. 10

    filter · Locked

    foodOnly

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11. 11

    find · Locked

    findByCategory

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12. 12

    References · Locked

    copy vs same

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13. 13

    Budget Report · Locked

    total + filter + remaining

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