[Doc] Taichi spec: static expressions (#4702)
[Doc] Taichi spec: static expressions (#4702)

* [Doc] Taichi spec: static expressions

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Update reference.md

Co-authored-by: pre-commit-ci[bot] <3ea08453efb076ca910552532a53973a6527df40@users.noreply.github.com>
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