Format

# FUNCTION_NAME ARG1 ARG2
# -----------------------
# MY_DESCRIPTION
# ...
# ...
FUNCTION_NAME () {
  MY_LOGIC
}

Example

See configure in CPython repo.

# as_fn_executable_p FILE
# -----------------------
# Test if FILE is an executable regular file.
as_fn_executable_p ()
{
  test -f "$1" && test -x "$1"
} # as_fn_executable_p