Octagram Labs
JavaScript
Data Structures
React
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JavaScript for React
0 of 70 solved
0%
x
Difficulty
all
▼
Status
all
▼
Immutable Arrays
0/10
○
Array State Reducer
medium
○
Move Item in a List
medium
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Add Item Immutably
easy
○
Remove by Index
easy
○
Update by Index
easy
○
Remove by Id
medium
○
Update by Id
medium
○
Insert at Index
medium
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Toggle Membership
medium
○
Move Item
medium
Immutable State
0/9
○
Apply a Sequence of Updates
medium
○
Update a Nested Field
medium
○
Set a Field
easy
○
Remove a Field
easy
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Update Nested Field
hard
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Merge State
easy
○
Toggle Boolean Field
medium
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Increment a Counter Field
easy
○
Reset Selected Fields
medium
Reducers
0/11
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Todo Reducer (full)
medium
○
Fold Actions over a Counter
easy
○
Cart Reducer with Quantities
medium
○
Todos Reducer
medium
○
Counter Reducer
easy
○
Add-by-Amount Reducer
easy
○
Todo Add Reducer
medium
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Todo Toggle Reducer
medium
○
Todo Remove Reducer
medium
○
Cart Reducer
hard
○
Form Reducer
medium
Rendering Lists
0/10
○
List Rendering Pipeline
medium
○
Group Items for Sectioned Lists
medium
○
Map to Labels
easy
○
Visible Items Only
easy
○
Sort by Name
medium
○
Extract Keys
easy
○
Paginate
medium
○
Page Numbers
medium
○
Group into Sections
medium
○
Chunk into Rows
medium
Derived State
0/8
○
Memoized Selector
hard
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Cart Summary (Derived, Not Stored)
medium
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Cart Total
easy
○
Count Completed
easy
○
Search Filter
medium
○
Active Count
easy
○
Percent Complete
medium
○
Summary Stats
medium
Props & Classes
0/7
○
Props and className Builder
medium
○
Merge Props with Defaults
medium
○
Props with Defaults
easy
○
classNames from Map
medium
○
Join Truthy Class Args
medium
○
Pick Props
medium
○
Conditional Class
easy
Events & Forms
0/8
○
Form Store
medium
○
Validate a Form
medium
○
Controlled Field Change
easy
○
Toggle Checkbox by Id
medium
○
Validate Required Fields
medium
○
Reset Form
easy
○
Count Errors
easy
○
Update from Synthetic Event
medium
Hooks Logic
0/7
○
Minimal Redux-style Store
hard
○
useCounter Logic
medium
○
useToggle Logic
easy
○
Pagination Slice
medium
○
useToggle Result
easy
○
Pagination State
medium
○
Apply Action Sequence
medium