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* Except perhaps Saxon which is still the no-longer-progressing Saxon-B, which is fine for now.
Use Smaller Files
Scala's compiler is quite slow, and an this must be taken into account to insure a reasonable edit-compile-debug cycle for developers. A compilation unit is an entire file. Incremental compilation is improved in efficiency if the files are smaller. So avoid huge files that blend multiple concepts together. Do not, however, go so far as to break things apart that really are best understood if kept in the same file.
Test-Driven Development & Design-for-Test (DFT)
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