xml.xpath(expression[, variables]) evaluates an XPath 1.0 expression
(https://www.w3.org/TR/1999/REC-xpath-19991116/) with the XML value as
the context node and returns the selected nodes as an XMLList, in
document order and without repeats. On an XMLList the expression runs
on each element in turn, and the results are joined.
- All 13 axes and the 27 core functions. id() selects nothing, since
E4X trees carry no DTD data.
- Each property of `variables` binds the variable of its name. A
prefix in a name test resolves through the context element's
in-scope namespaces; `xml` is always bound.
- An expression that breaks the grammar gives a SyntaxError. An
unknown function, a wrong argument count, an unbound prefix or
variable, a result that is not a node-set, and a result that holds
the root or a namespace node give a TypeError.
- The parser and the evaluator keep their state on their own stacks,
so expressions of any depth use no native stack; nesting past
Options::max_depth gives "nesting too deep". Traversal stacks, node
lists, strings and the values that string functions build count
against the heap limit, and every node visited and string read takes
fuel.
Docs: docs/target-app-parity.md (E4X line), crate doc in lib.rs.
A new built-in add-on, Image Tools (Object › Plug-ins › Image Tools),
adds Remove Background… (`addon.image.removeBackground`). It makes the
background of the selected images transparent by lowering the alpha of
their own pixels, in one undo step, with no service or model. The
background is the most common color along the image's edges, the
average of the image's corners, or colors the user picks. Contiguous
(on by default) clears it only where it reaches in from an edge; off,
it is cleared wherever it is. Tolerance and Softness (0 to 100, 10 by
default) set how near a color must be to be cleared and the band over
which pixels fade out. Match measures that nearness as the RGB
distance or as the largest difference on one channel. It is a
VectorCraft addition.
- The image stays an image: an embedded PNG with alpha, the source's
ICC profile and resolution, and 16 bits or gray when the source is.
A linked image is embedded and keeps its Placement Options.
- When the edges hold at least as many clear pixels as pixels of their
most common color, edge mode clears nothing, so a second run leaves
the subject alone. Corner mode leaves clear corners out of the
average and clears nothing when all four are clear.
- With Match set to Each Channel, a tolerance of t / 255 × 100 clears
the colors within t 8-bit steps on every channel.
- A CMYK image, a linked image that shows its preview, an image that
would need more than the decode allowance (checked from its header)
and a result with no pixel left are refused, and the document stays
as it was. When no pixel changes, no undo step is added. The result
reports `cleared`, the pixels made fully clear.
- Picked colors are hex colors, with or without `#`, or black, white,
red, green or blue.
- The dialog opens with Preview off; with Preview on, the canvas shows
the result, and Cancel puts the image back. While the dialog
previews, the session keeps the images' decoded pixels (at most
128 MiB, 32 MiB in the web app) so each preview step does not decode
them again, and releases them when the dialog closes with OK or
Cancel. A run that is not a preview step keeps nothing.
Docs: docs/mcp.md (Image Tools add-on), docs/target-app-parity.md.
A literal makes an extensible object whose properties are writable and
configurable, and an array whose length is writable. toSource wrote a
property defined with writable or configurable false, a sealed, frozen or
non-extensible object or array, and an array with a read-only length as an
ordinary literal, so evaluating the text gave an open value.
toSource now throws a TypeError for each of these, at any depth, as it
already does for getters, hidden properties and other prototypes.
Properties defined with every flag on are written as before.