Progress report in Pen programming language

February 6th, 2022

@raviqqe

Agenda

• Progress report
  • Hash map in standard package
  • Build system improvements
• Next plans

Progress report

Hash map in standard package (#676)

• Hash map is now available in a Core standard package!
• Implemented as a persistent data structure of Hash Array Mapped Trie (HAMT.)
  • Some optimizations are omitted for simplicity for now.
• It also provides maps specialized for string/number-only keys.

TestMapGet = \() none | error {
  key = "foo"
  value = "bar"

  m = map'Set(map'New(), key, value)

  Assert'True(map'Get(m, key) == value)
}

Build system improvements (#633, #702)

• Turtle build system is integrated into Pen!
• This change brings:
  • Completely comprehensive build output
  • Dependency cycle detection in build system
  • No workaround hack for Ninja's dynamic dependency bug

> pen build
resolving dependency of bar.pen
resolving dependency of foo.pen
dependency cycle detected: bar.pen -> foo.pen -> bar.pen
error: build failed

Even more...

• Reference count validation (#652)
• Bit module in a Core package (#673)
• Binary/hexadecimal number literals (#698)
• #![no_std] in Rust FFI libraries in Core and Prelude packages
• Several performance improvements

Next plans

• Multiple system packages in one application
  • std::process::exit function in Rust leaves async tasks in a tokio runtime...
• Join (select) operation for data parallel computation

Summary

• Hash map is added to the standard package.
• Incoming enhancements on practicality:
  • Multiple system packages
  • Join operation