`xs:ID` type of `id` attribute of `RunType` makes many mzml files starting with digits as file or sample name invalid. about mzml

[maximskorik]

Also, the main purpose of xs:ID type is to ensure a unique identifier for every XML element of that type. However, since the maxOccurs attr is not defined for the RunType, there can be only 1 run element per mzML, making the unique identifier unnecessary.

RunType definition in mzML1.1.0.xsd (where the maxOccurs is to be specified):

<xs:sequence>
  ...
  <xs:element name="run" type="dx:RunType" />
</xs:sequence>

from https://www.w3.org/TR/xmlschema-0/:
The default value for both the minOccurs and the maxOccurs attributes is 1.

Another reason why xs:ID might be needed is to have a target for IDREF or IDREFS attributes. However, I couldn't find any element that targets the ID of the run.

Thus, it appears that xs:ID may be safely replaced with xs:string. Note that switching the type to string will require adding a regexp to ensure the id doesn't contain any whitespaces.

[edeutsch]

Closing since addressed in PR #9