The Rust reference describes `?Sized` as "questionably sized". I feel vaguely judged :)
miniblog.
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Emacs 27, with harfbuzz for fonts, arbitrary sized ints, native JSON parsing, and portable dumping replacing unexec!
Component-Based Synthesis for Complex APIs: https://www.cs.utexas.edu/~isil/sypet-popl17.pdf
An incredible paper demonstrating synthesis of significantly sized pieces of Java code! You write a test case, and SyPet writes the code.
Today I learnt that Emacs defines a ring structure using just a fixed size array, to give you the convenience of circular structures and dynamically sized arrays!