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Migrating to Dotty
==================
### Minor tweaks ###
* `sym.linkedClassOfClass` => `sym.linkedClass`
* `definitions` => `ctx.definitions`
### Member Lookup ###
`tpe.member(name)` and `tpe.decl(name)` now return a `Denotation`, not a
`Symbol`. If no definition is found they return `NoDenotation` (instead of
`NoSymbol`).
### Symbol Properties ###
Most `sym.isProperty` methods don't exist in dotc, test for flags instead. See
[dotc vs scalac: Trees, Symbols, Types & Denotations]
### Logging, Error Reporting, Failures ###
There are various kinds of logging:
* Errors, warnings, etc: `ctx.inform`, `ctx.warning`, `ctx.error`, ...
* Log messages displayed under `-Ylog:phase`: `log(msg)` in scalac =>
`ctx.log(msg)` in dotc
* Debug-Log messages displayed under `-Ydebug -Ylog:<phase>`: `debuglog(msg)`
in scalac => `ctx.debuglog(msg)` in dotc
* Assertions: `assert(invariant)`
* Fatal errors: `abort(msg)` in scalac => `throw new
dotty.tools.dotc.FatalError(msg)` in dotc
#### During development / debugging ####
Instead of `Predef.println`, use `dotc.config.Printers.somePrinter.println`
[Printers.scala]. Printers can be easily added, enabled and disabled
without changing command line arguments.
```scala
val default: Printer = new Printer // new Printer => print
val core: Printer = noPrinter // noPrinter => shut up
```
[dotc vs scalac: Trees, Symbols, Types & Denotations]: https://github.com/lampepfl/dotty/wiki/dotc-vs-scalac:-Trees,-Symbols,-Types-&-Denotations
[Printers.scala]: https://github.com/lampepfl/dotty/blob/master/src/dotty/tools/dotc/config/Printers.scala
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