# Appendix A – Examples Of Valid Expressions

This appendix provides examples of expressions (both precoordinated and postcoordinated) which satisfy each of the expression constraints that were introduced in [https://github.com/SNOMED-Documents/snomed-expression-language/blob/main/appendix-a-examples-of-valid-expressions/broken-reference/README.md](https://github.com/SNOMED-Documents/snomed-expression-language/blob/main/appendix-a-examples-of-valid-expressions/broken-reference/README.md "mention"). This list of examples is not intended to be exhaustive, but rather to provide a representative sample to help clarify the meaning of each constraint. It is assumed that each particular usage of an expression constraint will clearly identify whether or not postcoordinated expressions are part of the valid substrate. Please refer to the [SNOMED CT Languages Github repository](https://github.com/IHTSDO/SNOMEDCT-Languages) for a set of text files containing each of these examples.

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