Strtr requires an array as the second argument?

I am calling code like

strtr($somevars['thisvar'], "abc")

Where $somevars['thisvar'] contains a string.

And it's giv开发者_JAVA技巧ing me

Warning:  strtr() [function.strtr]: The second argument is not an array

Why?

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Warning: strtr() [function.strtr]: The second argument is not an array

strtr != strstr

see: http://docs.php.net/strtr

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You have two possibilties for strtr:

string strtr ( string $str , string $from , string $to );

string strtr ( string $str , array $replace_pairs );

So even you add a third parameters and you can use a string, or you set an array and don't add a third parameter :)