An operation that keeps existing content, optionally modifying attributes.

Retain operations are used in changes (not documents) to indicate that content should be preserved. They can also apply or remove formatting.

Fields

• :target - Number of characters to retain, or embedded content for nested OT
• :attrs - Optional map of attribute changes to apply

Attribute Behavior

• Setting an attribute to a value applies that formatting
• Setting an attribute to nil removes that formatting
• Attributes not mentioned are left unchanged

Examples

# Keep 5 characters unchanged
%Otzel.Op.Retain{target: 5, attrs: nil}

# Keep 5 characters and make them bold
%Otzel.Op.Retain{target: 5, attrs: %{"bold" => true}}

# Keep 5 characters and remove bold
%Otzel.Op.Retain{target: 5, attrs: %{"bold" => nil}}

# Using helper function
Otzel.retain(5)
Otzel.retain(5, %{"bold" => true})