${cut("这是一个很长的字符串", 5)}

${cut("这是一个很长的字符串", 5, "...")}

${cut("这是一个很长的字符串", 7, 3)}

${cut('这是一个很长的字符串', 7, 3, "...")}

${cut(teststr, 7, "...")}

${testFunction(3, "'hello'", user.age)}
${testFunction(3, '"hello"', user.age)}
${testFunction2()}
${testXmlEscape}
${escape(testXmlEscape)}