From 02ca32ae0a5bc290918d2b2a3288e385b9cc6b11 Mon Sep 17 00:00:00 2001 From: Ralph Amissah Date: Fri, 19 Feb 2021 17:10:51 -0500 Subject: external & build dependences in src tree - external & build dependences boost licensed - ext_depends (external depends) - D-YAML - tinyendian - d2sqlite3 - imageformats - build_depends - dub2nix --- .../D-YAML/docs/articles/spec_differences.md | 64 ++++++++++++++++++++++ 1 file changed, 64 insertions(+) create mode 100644 src/ext_depends/D-YAML/docs/articles/spec_differences.md (limited to 'src/ext_depends/D-YAML/docs/articles') diff --git a/src/ext_depends/D-YAML/docs/articles/spec_differences.md b/src/ext_depends/D-YAML/docs/articles/spec_differences.md new file mode 100644 index 0000000..93cf038 --- /dev/null +++ b/src/ext_depends/D-YAML/docs/articles/spec_differences.md @@ -0,0 +1,64 @@ +# Differences between D:YAML and the YAML specification + +There are some differences between D:YAML and the YAML 1.1 +specification. Some are caused by difficulty of implementation of some +features, such as multiple Unicode encodings within single stream, and +some by unnecessary restrictions or ambiguities in the specification. + +Still, D:YAML tries to be as close to the specification as possible. It +should never load documents with different meaning than according to the +specification, and documents that fail to load should be very rare (for +instance, very few files use multiple Unicode encodings). + +## List of known differences: + +Differences that can cause valid YAML documents not to load: + + - No support for byte order marks and multiple Unicode encodings in a + stream. + + - Plain scalars in flow context cannot contain `,`, `:` and `?`. This + might change with `:` in the future. See + for details. + + - The specification does not restrict characters for anchors and + aliases. This may lead to problems, for instance, the document: + + [ *alias, value ] + + can be interpteted in two ways, as: + + [ "value" ] + + and: + + [ *alias , "value" ] + + Therefore we restrict aliases and anchors to ASCII alphanumeric + characters. + + - The specification is confusing about tabs in plain scalars. We don't + use tabs in plain scalars at all. + + - There is no support for recursive data structures in DYAML. + +Other differences: + + - Indentation is ignored in the flow context, which is less + restrictive than the specification. This allows code such as: + + key: { + } + + - Indentation rules for quoted scalars are loosed: They don't need to + adhere indentation as `"` and `'` clearly mark the beginning and the + end of them. + + - We allow `_` in tag handles. + + - Right now, two mappings with the same contents but different + orderings are considered unequal, even if they are unordered + mappings. This is because all mappings are ordered in the D:YAML + implementation. This should change in future, once D associative + arrays work with variant types or a map class or struct appears in + Phobos. -- cgit v1.2.3