Style-tag-registry-contains

Check whether a StyleTagRegistry contains one named tag. This is the boolean inspection companion to get(...) when code only needs existence rather than the stored style value.

Interface

pub fn StyleTagRegistry::contains(self : StyleTagRegistry, name : String) -> Bool {

input

• self : StyleTagRegistry - Registry to inspect.
• name : String - Tag name to check.

output

• Bool - true when the registry contains the tag, otherwise false.

Explanation

Detailed rules explaining key parameters and behaviors

• The tag name is normalized before the presence check.
• This method only checks the current registry value, not the global registry or builtin tag set.
• It is useful when code should branch on tag availability without unpacking TextStyle?.

How to Use

Here are some specific examples provided.

When Need A Simple Presence Check

When setup code should verify that a registry carries one custom tag:

let tags = style_tag_registry().set_tag("accent", fg=Some("#4cc9f0"))
println(tags.contains("accent"))

In this example, the result is true.

When Need To Guard Optional Registry Behavior

When later logic should only run for existing tags:

let tags = style_tag_registry()
if tags.contains("danger") {
  println("defined")
}

In this example, the guarded block runs only when the local registry already defines the tag.

Error Case

e.g.:

• Missing tags simply produce false.

• If code needs the actual stored style value, get(...) is the better API.

Notes

1. This is the lightest-weight way to probe one registry entry.

2. The method is useful in tests that only care about tag presence.