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Extensible integrals and brackets

See The Unicode Standard, Version 6.0,
§15.6 under Miscellaneous Technical → Use of Mathematical Symbol Pieces (esp. table 15-3)

Here special measures are taken in CSS to make HTML table cells align and connect properly.

Unclear how italics versions should function, or how they might function in any environment without strict horizontal spacing.

⌠

⎮

⌡

⎛ ⎜ ⎝

⎞ ⎟ ⎠

⎡ ⎢ ⎣

⎤ ⎥ ⎦

⎧ ⎪ ⎨ ⎪ ⎩

⎫ ⎪ ⎬ ⎪ ⎭

⎲

⎳