考虑下面的代码（Julia）
bar(x) = for i = 1:9999 x+x*x-x+x end # Define the "bar" function
print("First try: "); @time bar(0.5)
print("Second try: "); @time bar(0.5)
bar(x) = for i = 1:9999 x+x*x-x+x end # Redefine the same "bar" function
print("Third try: "); @time bar(0.5)
print("Fourth try: "); @time bar(0.6)
输出是
First try: elapsed time: 0.002738996 seconds (88152 bytes allocated)
Second try: elapsed time: 3.827e-6 seconds (80 bytes allocated)
Third try: elapsed time: 0.002907554 seconds (88152 bytes allocated)
Fourth try: elapsed time: 2.395e-6 seconds (80 bytes allocated)
为什么第二（第四）尝试比第一（第三）更快（占用更少的内存）？
据我了解，Julia具有即时编译器。因此，第一次（和第三次）运行是编译代码（具有所需的分配），而第二次（和第四次）运行只是运行先前编译的代码
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我来说两句