Bugs in the OMG materials

One place to look for defects found in the OMG-published sources this implementation consumes, outside the training corpus. Corpus files are adjudicated per file in training-examples.md; this page records defects in the vendored specification libraries (internal/core/libs/stdlib/), where the declaration is wrong rather than a model using it.

Each row quotes the vendored declaration verbatim so a reviewer can judge it without opening the library, and names what OpenSysML implements instead. Every divergence is also a row in spec-compliance.md.

Library file	Declaration	What the vendored body says	What we implement	Why
Kernel Libraries/Kernel Function Library/SequenceFunctions.kerml	function includingAt	(seq->subsequence(1, index - 1), values, seq->subsequence(index + 1)) — the prefix before index, then the values, then the tail from index + 1, so the element at index is dropped from the result	insertion: the values are inserted before the 1-based index, the tail from that position shifts right, and the result is longer than seq by the values inserted. index == size + 1 appends; any other index outside 1..size + 1 is ErrIndexOutOfRange (runtime.builtinSequenceIncludingAt)	The body contradicts the declarations around it in the same file. excludingAt is the operation that removes at an index, and the behavior pairs are additive/subtractive: add calls including as remove calls excluding, and addAt calls includingAt (seq->includingAt(values, index)) as removeAt calls excludingAt. A removing includingAt would leave the library with two ways to delete at an index and none to insert at one, and would make addAt remove. The vendored expression is an off-by-one slip in the tail: the insertion body is (seq->subsequence(1, index - 1), values, seq->subsequence(index))

includingAt — the vendored declaration

Quoted verbatim from internal/core/libs/stdlib/Kernel Libraries/Kernel Function Library/SequenceFunctions.kerml:

function includingAt{ in seq: Anything[0..*] ordered nonunique; in values: Anything[0..*] ordered nonunique;
    in index: Positive[1];
    return : Anything[0..*] ordered nonunique =
        (seq->subsequence(1, index - 1), values, seq->subsequence(index + 1));
}

subsequence(1, index - 1) is the prefix ending before index, and subsequence(index + 1) is the tail starting after index; the element at index appears in neither, so evaluating the body as written replaces it with values rather than inserting before it. OpenSysML implements insertion (maintainer ruling, PR for task S4), so includingAt is a divergence from the vendored body and is recorded here for review against a future OMG release.