Work with ranges of the tree

A Range marks a run of the tree between two boundary points and copies, moves, deletes, or wraps everything between them. Each boundary is a (container, offset) pair: the offset indexes the container’s children, or its code points when the container is character data. Build one with a starting boundary, then move the end.

Copy or move a run of siblings

clone_contents() returns a fragment copying the range without touching the tree; extract_contents() moves the nodes out into the fragment instead, leaving the range collapsed:

from turbohtml import Range

doc = turbohtml.parse("<ul><li>a</li><li>b</li><li>c</li></ul>")
ul = doc.find("ul")
span = Range(ul, 0)
span.set_end(ul, 2)
moved = span.extract_contents()
print(moved.html)
print(ul.html)

<li>a</li><li>b</li>
<ul><li>c</li></ul>

Delete part of a text node

A boundary inside a Text node offsets by code point, so the same string index you would slice with addresses the boundary. delete_contents() splices the run out:

doc = turbohtml.parse("<p>Hello brave World</p>")
text = doc.find("p").children[0]
span = Range(text, 6)
span.set_end(text, 12)
span.delete_contents()
print(doc.find("p").html)

<p>Hello World</p>

Wrap a selection

surround_contents() extracts the range, wraps it in a new parent, and puts the parent back where the range was – splitting the surrounding text as needed:

from turbohtml import Element

doc = turbohtml.parse("<p>one two three</p>")
text = doc.find("p").children[0]
span = Range(text, 4)
span.set_end(text, 7)
span.surround_contents(Element("em"))
print(doc.find("p").html)

<p>one <em>two</em> three</p>

Insert a node at a boundary

insert_node() places a node at the range’s start. When that start sits inside a text node the text splits around it:

doc = turbohtml.parse("<div><p>x</p></div>")
box = doc.find("div")
Range(box, 1).insert_node(Element("hr"))
print(box.html)

<div><p>x</p><hr></div>

Where a live Range shifts its own boundaries as its content operations run, a StaticRange is a fixed snapshot – the four boundary values with the collapsed flag and nothing else:

from turbohtml import StaticRange

box = doc.find("div")
snapshot = StaticRange(box, 0, box, len(box.children))
print(snapshot.collapsed, snapshot.end_offset)

False 2