Inspecting Compiled Output with show

show prints fully typechecked package data as EDN. It is useful when you want to inspect what Bosatsu inferred and what the compiler is lowering. Use --json when you want machine-readable output for tooling.

Quick examples

All commands below assume running from this repository root.

Show a whole package

./bosatsuj show --name core_alpha --package Bosatsu/Char --color none

This prints one (package ...) form with sections like :imports, :types, :externals, and :defs.

Emit JSON instead of EDN

./bosatsuj show --name core_alpha --package Bosatsu/Char --json

--json emits a deterministic JSON projection of the same show data. The top-level value is an object with "$form": "show" and fields such as ir, typed-passes, and packages. Typed output also includes interfaces.

Show Matchless IR instead of typedexpr

./bosatsuj show --name core_alpha --package Bosatsu/Char --ir matchless --color none

This lowers the selected package to Matchless before rendering. The top-level show form reports :ir matchless and :matchless-passes. Matchless output is intentionally value-only: it omits typed sections such as :interfaces and package :types.

Show a single type

./bosatsuj show --name core_alpha --type Bosatsu/Option::Option --color none

Use --type <package::Type> when you only want one type definition instead of the full package.

Show a single value

./bosatsuj show --name core_alpha --value Bosatsu/Num/Binary::not --color none

Use --value <package::value> to focus on one top-level value. This selects values that exist in compiled package output. If a helper value is fully inlined or otherwise eliminated, it will not be available by name.

If you want to inspect values before a pass erases them, disable the relevant pass explicitly:

./bosatsuj show --name core_alpha \
  --value Bosatsu/Num/Binary::helper \
  --disable-typed-pass discard-unused \
  --color none

You can mix selectors:

./bosatsuj show --name core_alpha \
  --package Bosatsu/Char \
  --type Bosatsu/Option::Option \
  --value Bosatsu/Num/Binary::not \
  --color none

If no --package, --type, or --value is given, show shows all local library packages (the existing default behavior).

Pass controls

Typed output keeps the current fixed pass order and lets you disable stages individually:

./bosatsuj show --name core_alpha \
  --package Bosatsu/FibBench \
  --disable-typed-pass loop-recur-lowering \
  --disable-typed-pass normalize \
  --color none

library show still accepts --no-opt as a compatibility alias for disabling all typed passes at once.

Matchless output supports three named stages:

./bosatsuj show --name core_alpha \
  --package Bosatsu/Char \
  --ir matchless \
  --disable-matchless-pass hoist-invariant-loop-lets \
  --disable-matchless-pass reuse-constructors \
  --color none

To inspect Matchless before and after namespace-level inlining, toggle global-inlining:

./bosatsuj show --name core_alpha \
  --value Bosatsu/FibBench::fib \
  --ir matchless \
  --disable-matchless-pass global-inlining \
  --color none

./bosatsuj show --name core_alpha \
  --value Bosatsu/FibBench::fib \
  --ir matchless \
  --color none

The first command shows raw lowered Matchless with local cleanup only. The second shows the default Matchless pipeline, including global inlining.

Why this helps

See inferred types on values

Entries in :defs include typed expressions, so you can inspect the inferred type information attached to each value.

See tail-recursive lowering shape

When tail recursion is optimized, show exposes loop-like forms such as loop/recur in the typed expression. For example:

./bosatsuj show --name core_alpha --package Bosatsu/FibBench --color none

In that package, the source helper list_len is inlined into another compiled definition, and you can still see the loop-like lowered shape there. This is a practical way to confirm code that should compile to loops in backends.