$display-breakpoints: map-deep-merge(
  (
    "sm-only": "only screen and (min-width: #{$map-get + $grid-breakpoints + "hogehoge"}) and (max-width: #{$a})",
    "sm-only": "inside a long long long long long long long long long long long long long long string #{call("")}",
    "sm-only": "inside a long long long long long long long long long long long long long long string #{$foo} and #{call("")}",
    "sm-only": "inside a long long long long long long long long long long long long long long string #{call($a)}",
  ),
  $display-breakpoints
);

@each $name, $hue in $hues {
  $map: map.merge(
    $map,
    (
      '#{$prefix}-#{$name}': blend.set($base, $hue: $hue),
    )
  );
}