Python の t-strings はコマンドラインの構成に使える

from collections.abc import Iterable
from string.templatelib import Template, Interpolation, convert


def iformat(interpolation: Interpolation, /) -> str:
  obj = convert(interpolation.value, interpolation.conversion)
  return format(obj, interpolation.format_spec)


def template_to_cmds(template: Template) -> list[str]:
  args: list[str] = []
  pre_continuation, post_interpolation = False, False
  for part in template:
    match part:
      case str() as static_part:
        cmds = build_cmds(static_part)
        continuation = ("\0" + static_part).split()[0] != "\0"
        if post_interpolation and continuation:
          args[-1] = args[-1] + cmds[0]
          args.extend(cmds[1:])
        else:
          args.extend(cmds)
        pre_continuation = (static_part + "\0").split()[-1] != "\0"
        post_interpolation = False
      case interpolation:
        fstr = iformat(interpolation)
        if pre_continuation:
          args[-1] = args[-1] + fstr
        else:
          args.append(fstr)
        post_interpolation = True
  return args


def build_cmds(*cmdline_or_arglist: str | Iterable[str] | Template) -> list[str]:
    args: list[str] = []
    for arg in cmdline_or_arglist:
      match arg:
        case Template() as template:
          args.extend(template_to_cmds(template))
        case str() as cmdline:
          cmds = cmdline.split()
          args.extend(cmds)
        case Iterable():
          args.extend(arg)
        case _:
          raise TypeError(f"Invalid argument: {arg!r}")
    return args