Opaque type representing terminal output. Built from primitives, rendered by the framework.

Unstyled text.

Stack screens vertically. Each item starts on a new line.

Concatenate screens horizontally, row by row. If one child has more lines than another, the extra trailing lines are preserved.

Empty screen that renders nothing and takes up zero lines. Use this as a "null" value, for example with Maybe.withDefault:

case maybeError of
    Just err ->
        Screen.text err |> Screen.fg Ansi.Color.red


    Nothing ->
        Screen.empty

Note: this is different from blank which renders one empty line. empty produces no output at all.

A blank line that renders one empty line. Useful as a vertical spacer in lines:

Screen.lines
    [ Screen.text "Title"
    , Screen.blank
    , Screen.text "Content"
    ]

Note: this is different from empty which renders nothing. blank produces a visible gap (one empty row).

Set foreground color on a Screen. Composes with pipeline syntax:

Screen.text "error" |> Screen.fg Ansi.Color.red


Screen.text "warning" |> Screen.fg Ansi.Color.yellow |> Screen.bold

Set background color on a Screen.

Screen.text "selected" |> Screen.bg Ansi.Color.blue

Apply bold attribute.

Screen.text "important" |> Screen.bold

Apply dim attribute.

Screen.text "muted" |> Screen.dim

Apply italic attribute.

Apply underline attribute.

Apply strikethrough attribute.

Apply inverse (reverse video) attribute.

Apply a list of attributes at once. Useful when the attribute set is dynamic (from a config, theme, or computed list). Equivalent to chaining the individual builders.

import Tui.Attribute as Attr
import Tui.Screen as Screen


Screen.text "Heading"
    |> Screen.withAttributes [ Attr.Bold, Attr.Underline ]

Wrap a Screen in a clickable hyperlink (OSC 8). In terminals that support it, the text becomes a clickable link. In unsupported terminals, the escape sequence is silently ignored and the text renders normally.

Screen.text "elm/core"
    |> Screen.underline
    |> Screen.fg Ansi.Color.blue
    |> Screen.link { url = "https://package.elm-lang.org/packages/elm/core/latest" }

Terminal cell style: foreground color, background color, text attributes, and optional hyperlink.

Opaque so the field list can grow in future releases without breaking user code. To build styled text, use the Screen-level builders (fg, bold, etc.) directly on a Screen. To read the style of a Tui.Screen.Advanced.Span, use Tui.Screen.Advanced.styleForeground and friends.

Truncate a Screen to a maximum width in columns, preserving styles. Adds "\u{2026}" if truncated. Works on the first line only. Returns empty for non-positive widths.

Wrap a Screen to a maximum width, preserving styles across line breaks. Returns a list of Screens, one per wrapped line.

Screen.concat
    [ Screen.text "This is a "
    , Screen.text "very important" |> Screen.bold
    , Screen.text " paragraph about decoding JSON values."
    ]
    |> Screen.wrapWidth 30
-- Returns 3 Screens with "very important" still bold

Wraps at word boundaries (spaces). Words longer than maxWidth are broken mid-word. Existing line breaks are preserved. Returns [] for empty screens or non-positive widths.

Convert a Screen to a plain text string (no ANSI codes). Useful for testing, layout measurement, and debugging.