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Version 0.4.2 of the CIF API has now been released. It is available at the GitHub site , as usual, or a full distribution can be obtained directly from me. Changes from versions 0.4.0 and 0.4.1 are mostly bug fixes, but experimental program cif_linguist received a major improvement to its whitespace...

I am pleased to announce the release of CIF API 0.3.0. This is the first public, production release of the CIF API. Notable changes from beta test release 0.2.0 include: ⋅  CIF API is now offered for use under the terms of the GNU LGPL. ⋅  Type name change : because POSIX reserve...

I am pleased to announce the release of CIF API version 0.2.0 for beta testing. Among the CIF API's high-level features are ⋅  a fully-functional CIF 1.1/2.0 autodetecting parser, operating either to ⋅  parse to an in-memory whole-CIF representation (analogous to DOM XML parsers...

I agree with John's proposal to allow whitespace around the full colon in tables. As the key is a delimited string, detecting the end of the key is not dependent on an immediately following full colon, and likewise, there is no ambiguity introduced by allowing whitespace after the full colon. Altho...

We need a way to handle different isotopes, which have wildly different scattering lengths for neutrons. I propose simply adding _atom_type_atomic_weight to this category in order to allow description of different isotopes. I recommend _atom_type_mass_number or _atom_type_isotope_mass_number instea...

For the record, I observe that although the parser will flag an error if the key of a table entry is bare or is a text block instead of being a quoted string, its recovery path from such errors will accept those keys. In the case of bare keys, the key is interpreted to end at the first colon, if the...

The more general "around" alternative does solve the problems I described, however, and it's what Nick at one point claimed was the original intent. I'll see how that goes. For the curious: I have set up the parser to allow whitespace on both sides of the colon in a table entry, and in th...

I agree with John's proposal to allow whitespace around the full colon in tables. As the key is a delimited string, detecting the end of the key is not dependent on an immediately following full colon, and likewise, there is no ambiguity introduced by allowing whitespace after the full colon. Hmmm....

It is my interpretation of the changes document and of the DDLm working group archives that it is not syntactically correct for whitespace to appear between key and separating colon or between colon and value of a table entry in a CIF 2 document. This is a bit ticklish, however, because the values i...

While working on details of the CIF API's lexical scanner, I have discovered a couple of possible ambiguities with respect to where comments are allowed. Below I document the issue and how I have chosen to handle it in the scanner, but if anyone thinks the specs demand a different interpretation the...