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+## std.debug: Useful functions for debugging.
+## This module is imported by default.
+
+## The special ... syntax is used to mark unimplemented parts of code.
+## Such code will compile, but panic upon being called at runtime.
+## It is usable almost anywhere, including in type declarations, thanks to compiler magic.
+pub func ...: never
+
+## The `assert` macro checks that a provided assertation is true,
+## and panics and dumps information if it is not.
+## Asserts remain in release builds. If not desired, see `debug_assert`
+pub macro assert(cond: bool) =
+  quote:
+    if not `cond`:
+      panic "assertation failed!\n {}".fmt(dbg(`cond`))
+
+## The `debug_assert` function provides an assert that is compiled out in release builds.
+## This is useful for debugging performance-critical code.
+pub macro debug_assert(cond: bool)
+  quote:
+    when debug: # fixme: where is this coming from?
+      assert `cond`
+
+## The `discard` function consumes any type.
+## Useful for throwing away the result of a computation.
+pub func discard[T](self: T) =
+  return
+
+## The `panic` function prints a message to `stderr` and quits.
+pub func panic(message: str): never =
+  stderr.write(message, "\n")
+  std.os.exit(1)