php - 我收到 "syntax error, unexpected T_VARIABLE"错误。我不明白我做错了什么？

Question

我收到这个错误:“PHP 解析错误:语法错误，第 66 行/var/www/vhosts/... 中的意外 T_VARIABLE”

这是我的代码:

function combine($charArr, $k) {

    $currentsize = sizeof($charArr);
    static $combs = array();
    static $originalsize = $currentsize; ###### <-- LINE 66 ######
    static $firstcall = true;

    if ($originalsize >= $k) {

        # Get the First Combination 
        $comb = '';
        if ($firstcall) { //if this is first call
            for ($i = $originalsize-$k; $i < $originalsize; $i++) {
                $comb .= $charArr[$i];
            }
            $combs[] = $comb; //append the first combo to the output array
            $firstcall = false; //we only want to do this during the first iteration
        }
    ....
    ....
}

知道哪里出了问题吗？

Answer 1

引用 the manual (该页面是关于静态属性的，但同样适用于变量):

Like any other PHP static variable, static properties may only be initialized using a literal or constant; expressions are not allowed. So while you may initialize a static property to an integer or array (for instance), you may not initialize it to another variable, to a function return value, or to an object.

你正在使用这个:

static $originalsize = $currentsize;

这是用表达式初始化的——而不是常量。

这是the manual's section这与静态变量完全相同:

Static variables may be declared as seen in the examples above. Trying to assign values to these variables which are the result of expressions will cause a parse error.

为了以防万一，这里是about expressions .

在你的情况下，为了避免这个问题，我想你可以修改你的代码，所以它看起来像这样:

$currentsize = sizeof($charArr);
static $originalsize = null;
if ($originalsize === null) {
    $originalsize = $currentsize;
}

有了那个:

• 静态变量用常量初始化
• 如果它的值是常量，分配动态值。