capitalize[首字母大写]
count_characters[计算字符数]
cat[连接字符串]
count_paragraphs[计算段落数]
count_sentences[计算句数]
count_words[计算词数]
date_format[时间格式]
default[默认]
escape[转码] html,hemlall,url
indent[缩进]
lower[小写]
replace[替换]
regex_replace[正则替换]
spacify[插空]
string_format[字符串格式化]数字 %.2f
strip[去除（多余空格）]
strip_tags[去除HTML标签]
truncate[截取]
upper[大写]
wordwrap[行宽约束]