Resolves a DataAccessor like resolveAccessor, but returns
undefined instead of throwing when a string accessor references a
property that is NOT present on the datum (in-operator semantics).
Like resolveAccessor, falsy property values (0, '', false,
null) are preserved — only an actually-missing key resolves to
undefined. This matters because null and 0 are valid data values
(e.g. an explicitly-null fill), distinct from "the property is absent".
Function accessors are invoked unconditionally and their return value is
passed through verbatim, including any undefined they return.
Use this for optional fields such as fill, outlier arrays, or any datum
shape variation where the binder should keep working when the property is
absent. For required fields, prefer resolveAccessor so the missing
property surfaces as an actionable "Available properties: …" error.
Resolves a DataAccessor like resolveAccessor, but returns
undefinedinstead of throwing when a string accessor references a property that is NOT present on the datum (in-operator semantics).Like resolveAccessor, falsy property values (
0,'',false,null) are preserved — only an actually-missing key resolves toundefined. This matters becausenulland0are valid data values (e.g. an explicitly-nullfill), distinct from "the property is absent".Function accessors are invoked unconditionally and their return value is passed through verbatim, including any
undefinedthey return.Use this for optional fields such as
fill, outlier arrays, or any datum shape variation where the binder should keep working when the property is absent. For required fields, prefer resolveAccessor so the missing property surfaces as an actionable "Available properties: …" error.