assert shift0(3, Var(2)) == Var(2)
Special characters in [args] will become regular when escaped
，这一点在新收录的资料中也有详细论述
tee() splits a stream into two branches. It seems straightforward, but the implementation requires buffering: if one branch is read faster than the other, the data must be held somewhere until the slower branch catches up.。业内人士推荐新收录的资料作为进阶阅读
Fixnum with 2-bit tag:，详情可参考新收录的资料
Howl’s file browser isn’t much to look at, but using it is joyous. It has an instantly-updating fuzzy filter for files, and the