DSL2 Coding guidelines and best practices

Disclaimer

We're trying to forge the best practices
- Syntax and/or logic might (and probably will) evolve

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It's useful for:
- 👉 future you 👈
- your collaborators
- whoever will look at your code at any point

Use if logic in the main workflow
- or even better branch, which follows the data flow paradigm
All subworkflows should be simpler and have no need for such logic
- Use when in modules.config to control modules
  - Expect if too many empty process thant clutter the terminal
  - Then ok to use if

Use explicit channel assignment rather than .set{} for readability. E.g.,

ch_foo = ch_bar.map{ meta, baz -> [baz] }

is easier to identify input/output than

ch_bar.map{ meta, baz -> [baz] }.set{ ch_foo }

script:
def inputs = input.collect{"-I $it"}.join(' ')
"""