Implicits Inspected and Explained
summary
Step-by-step demos use the Represent REPL and JavaP bytecode to show that implicits get filled into calls at compile time and disappear from generated bytecode; examples include actor ! with an implicit sender, Future with implicit ExecutionContext, Numeric[T] for sum, and a Finagle client builder that requires three implicit "client config evidence" pieces and fails compilation with Builder is not fully configured via @implicitNotFound. The resolution follows implicit scope rules: local simple-name, companion/package objects, supertypes. Implicit conversions do not chain (only one conversion is applied).
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chapters (8)
- 0:00Implicits in Scala
- 6:32Power of implicits
- 8:44Implicit parameters
- 17:37Implicit conversions
- 23:04Implicit classes
- 25:34Compiler resolution
- 33:26Type classes benefits
- 44:30Summary
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