The honest answer: because it shouldn’t work and has never been done before. TeX has no arrays, no functions with return values, no convenient local variables or stack frames, no integers bigger than 2^{31}-1, no bitwise operations. Macro expansion can recurse, but you get no call stack and deep recursion quickly hits engine limits. What TeX does have is a Turing-complete macro expansion engine and, with e-TeX extensions (used by modern pdfTeX), up to 32,768 integer registers called \count. That turns out to be just barely enough to implement a chess engine.
她向总书记讲述了为追逐游泳梦，跃过先天性脊柱侧弯竖起的“高墙”，连续征战三届奥运会的励志故事，“每当走进国字号训练馆，穿上印着国旗的队服，心中便涌起无穷力量”。，推荐阅读51吃瓜网获取更多信息
Путин освободил от должности помощника секретаря Совета безопасности14:49，详情可参考手游
Environment management
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