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`format_attrs` function

format_attrs(attrs: Mapping[str, Any]) -> Markup

Format an attribute dict into an HTML attribute string.

True renders the bare attribute (disabled); False and None omit the attribute entirely.
class and style values may use the structured forms; they are normalized here, so merge_attrs output and hand-built dicts render the same. An empty class or style is omitted.
Everything else renders key="value", escaped; values with __html__ pass through unescaped.

Example::

format_attrs({
    "class": ["btn", {"active": True}],
    "disabled": True,
    "data-id": 3,
})
# -> 'class="btn active" disabled data-id="3"'

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`merge_attrs` function

merge_attrs(*attrs_dicts: Mapping[str, Any] = ()) -> dict[str, Any]

Merge attribute dicts left to right into one dict.

Every key resolves last-one-wins, except class and style: their values from all dicts are collected and combined per normalize_class / normalize_style, so several sources can contribute classes and style properties without overwriting each other.

Key order in the result is the order each key was first seen, so a later override does not move an attribute.

Example::

merge_attrs(
    {"class": "btn", "id": "first"},
    {"class": {"active": True}, "id": "second"},
)
# -> {"class": "btn active", "id": "second"}

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`normalize_class` function

normalize_class(value: ClassValue) -> str

Turn a structured class value into a plain class string.

A string is used as-is (stripped).
A dict keeps only the keys whose value is truthy.
A list may mix strings, dicts, and nested lists. Each item converts to a {class_name: bool} dict (strings split on whitespace, all True) and the dicts merge left to right, so a later falsy entry removes a class added earlier.

Example::

normalize_class(["btn btn-lg", {"active": True, "hidden": False}])
# -> "btn btn-lg active"

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`normalize_style` function

normalize_style(value: StyleValue) -> str

Turn a structured style value into an inline CSS string.

A string is used as-is (stripped).
A dict renders each entry as property: value;. Property names are used as written (kebab-case); numbers render bare (width: 100).
A list may mix strings, dicts, and nested lists. Strings are parsed into property dicts (see parse_string_style) and the dicts merge left to right, so the last value of a property wins.

Two special values steer a merge: None skips the entry (an earlier value for the property stands), and a literal False removes the property entirely, even if set earlier.

Example::

normalize_style(["color: red; width: 100px", {"color": "green", "width": False}])
# -> "color: green;"

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`parse_string_style` function

parse_string_style(css_text: str) -> dict[str, Any]

Parse an inline CSS string into a property dict.

Strips /* ... */ comments. Declarations split on ; except inside parentheses, so url(data:image/png;base64,...) survives. A declaration without a : is dropped.

Example::

parse_string_style("color: red; width: 100px; /* note */")
# -> {"color": "red", "width": "100px"}

format_attrs function

merge_attrs function

normalize_class function

normalize_style function

parse_string_style function

`format_attrs` function

`merge_attrs` function

`normalize_class` function

`normalize_style` function

`parse_string_style` function