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Syntax Essentials
Variables by assignment String interpolation Arrays Objects Existential operator ? Soaked access ?. Ranges Destructuring assignment Splats Comments
Functions
Function arrow -> Bound arrow => Implicit return Default parameters Rest parameters Named functions Higher-order functions IIFE with do Function composition Callbacks
Control Flow
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Iteration
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Classes
class declaration constructor Instance methods Static methods extends super Bound instance methods Prototype access :: Class properties Mixins with object assignment
Operators
is and isnt and or not in operator of operator Chained comparisons Floor division // Modulo %% Exponentiation ** Assignment operators Nullish assignment ?=
JavaScript Interop
Embedded JavaScript require modules ES module import ES module export Promise usage async functions await JSON parsing DOM querySelector Event listeners
Patterns & Practical Code
Memoization Guard clauses Object defaults Optional callbacks Configuration merge Grouping values Flattening arrays Unique values Sorting objects Error wrapping
CoffeeScript Complete Course / Patterns & Practical Code

Error wrapping

Learn Error wrapping in CoffeeScript with a construct-specific explanation, a unique example, a practical boundary, and a mastery check.

12 min read • Advanced

Error wrapping is an atomic CoffeeScript topic inside Patterns & Practical Code. The example below uses the actual construct named by the lesson rather than a generic placeholder.

Focus on what Error wrapping changes: the input, binding, control path, object state, collection, runtime effect, or language contract. Then alter one value and verify that the behavior changes for a reason specific to this feature.

Topic-specific example

coffeescript-08-10-error-wrapping.coffee
coffeescript Try It Live 
load = ->
  try
    throw new Error "disk"
  catch err
    throw new Error "load failed: #{err.message}"
try load() catch err then console.log err.message
Edge case / engineering note

Exercise both the success path and the failure path; verify what is caught, propagated, or cleaned up rather than only checking printed output.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

Error wrapping Mastery Check →
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Sorting objects