无法在R

Question

我和R玩弄了一下，我很想知道为什么这不起作用：

#! /usr/bin/Rscript

# initializes function
s <- function() {
    return(0);
};

# run function to see it's there (should return 0)
s();

while (s() != 12) {

    # print function to see its contents
    print(s);

    # rewrite function, hopefully it will return 12 now
    s <- paste("function() {",
               "return(",
               sample(1:100,1),
               "+",
               sample(1:100,1),
               ")",
               "}"
    )
}

print(solve);

输出结果为：

dooh@dooh:~$ '/home/dooh/Desktop/solve.R/solve.R' 
[1] 0
function () 
{
    return(0)
}
Error: could not find function "s"
Execution halted

不知何故，s变成了一个字符串，并且不再作为一个函数存活 - 因此，while之后的评估将永远不会返回12.我怎样才能强制执行字符串进入一个功能？

Answer 1

请改为尝试：

s <- function() {
        return(0);
};

# run function to see it's there (should return 0)
s();

while (s() != 12) {

        # print function to see its contents
        print(s);

        # rewrite function, hopefully it will return 12 now
        s <- as.function(alist(sample(1:100,1)+sample(1:100,1)))

        }