我正在使用gettext javascript解析器,而且我仍然坚持使用解析正则表达式。
我需要捕获传递给特定方法调用_n(
和_(
的每个参数。例如,如果我在我的javascript文件中有这些:
_("foo") // want "foo"
_n("bar", "baz", 42); // want "bar", "baz", 42
_n(domain, "bux", var); // want domain, "bux", var
_( "one (optional)" ); // want "one (optional)"
apples === 0 ? _( "No apples" ) : _n("%1 apple", "%1 apples", apples) // could have on the same line two calls..
这引用了此文档:http://poedit.net/trac/wiki/Doc/Keywords
我计划两次(以及两个正则表达式):
_n(
或_(
方法调用的所有函数参数基本上,我想要一个正则表达式,可以说"捕捉_n(
或_(
后的所有内容,并在最后一个括号)
停止功能已完成。如果可以使用正则表达式并且没有javascript解析器,我不知道。
还可以做的是"捕获每个"字符串"或者'字符串'在_n(
或_(
之后,在该行的结尾处或在新的_n(
或_(
字符的开头停止。
在我完成的所有事情中,我要么被_( "one (optional)" );
括在内侧括号内,要么apples === 0 ? _( "No apples" ) : _n("%1 apple", "%1 apples", apples)
在同一行上有两次调用。
这是我到目前为止实施的,具有不完美的正则表达式:generic parser和javascript one或handlebars one
答案 0 :(得分:8)
注意: Read this answer如果您不熟悉递归。
谁说正则表达式不能模块化?那么PCRE正在拯救!
~ # Delimiter
(?(DEFINE) # Start of definitions
(?P<str_double_quotes>
(?<!\\) # Not escaped
" # Match a double quote
(?: # Non-capturing group
[^\\] # Match anything not a backslash
| # Or
\\. # Match a backslash and a single character (ie: an escaped character)
)*? # Repeat the non-capturing group zero or more times, ungreedy/lazy
" # Match the ending double quote
)
(?P<str_single_quotes>
(?<!\\) # Not escaped
' # Match a single quote
(?: # Non-capturing group
[^\\] # Match anything not a backslash
| # Or
\\. # Match a backslash and a single character (ie: an escaped character)
)*? # Repeat the non-capturing group zero or more times, ungreedy/lazy
' # Match the ending single quote
)
(?P<brackets>
\( # Match an opening bracket
(?: # A non capturing group
(?&str_double_quotes) # Recurse/use the str_double_quotes pattern
| # Or
(?&str_single_quotes) # Recurse/use the str_single_quotes pattern
| # Or
[^()] # Anything not a bracket
| # Or
(?&brackets) # Recurse the bracket pattern
)*
\)
)
) # End of definitions
# Let's start matching for real now:
_n? # Match _ or _n
\s* # Optional white spaces
(?P<results>(?&brackets)) # Recurse/use the brackets pattern and put it in the results group
~sx
s
用于将换行符与.
匹配,x
修饰符用于我们正则表达式的这种奇特的间距和注释。
Online regex demo Online php demo
由于我们的正则表达式也会得到开始和结束括号()
,我们可能需要过滤它们。我们将在结果中使用preg_replace()
:
~ # Delimiter
^ # Assert begin of string
\( # Match an opening bracket
\s* # Match optional whitespaces
| # Or
\s* # Match optional whitespaces
\) # Match a closing bracket
$ # Assert end of string
~x
所以这是另一个模块化正则表达式,你甚至可以添加自己的语法:
~ # Delimiter
(?(DEFINE) # Start of definitions
(?P<str_double_quotes>
(?<!\\) # Not escaped
" # Match a double quote
(?: # Non-capturing group
[^\\] # Match anything not a backslash
| # Or
\\. # Match a backslash and a single character (ie: an escaped character)
)*? # Repeat the non-capturing group zero or more times, ungreedy/lazy
" # Match the ending double quote
)
(?P<str_single_quotes>
(?<!\\) # Not escaped
' # Match a single quote
(?: # Non-capturing group
[^\\] # Match anything not a backslash
| # Or
\\. # Match a backslash and a single character (ie: an escaped character)
)*? # Repeat the non-capturing group zero or more times, ungreedy/lazy
' # Match the ending single quote
)
(?P<array>
Array\s*
(?&brackets)
)
(?P<variable>
[^\s,()]+ # I don't know the exact grammar for a variable in ECMAScript
)
(?P<brackets>
\( # Match an opening bracket
(?: # A non capturing group
(?&str_double_quotes) # Recurse/use the str_double_quotes pattern
| # Or
(?&str_single_quotes) # Recurse/use the str_single_quotes pattern
| # Or
(?&array) # Recurse/use the array pattern
| # Or
(?&variable) # Recurse/use the array pattern
| # Or
[^()] # Anything not a bracket
| # Or
(?&brackets) # Recurse the bracket pattern
)*
\)
)
) # End of definitions
# Let's start matching for real now:
(?&array)
|
(?&variable)
|
(?&str_double_quotes)
|
(?&str_single_quotes)
~xis
我们将循环并使用preg_match_all()
。最终代码如下所示:
$functionPattern = <<<'regex'
~ # Delimiter
(?(DEFINE) # Start of definitions
(?P<str_double_quotes>
(?<!\\) # Not escaped
" # Match a double quote
(?: # Non-capturing group
[^\\] # Match anything not a backslash
| # Or
\\. # Match a backslash and a single character (ie: an escaped character)
)*? # Repeat the non-capturing group zero or more times, ungreedy/lazy
" # Match the ending double quote
)
(?P<str_single_quotes>
(?<!\\) # Not escaped
' # Match a single quote
(?: # Non-capturing group
[^\\] # Match anything not a backslash
| # Or
\\. # Match a backslash and a single character (ie: an escaped character)
)*? # Repeat the non-capturing group zero or more times, ungreedy/lazy
' # Match the ending single quote
)
(?P<brackets>
\( # Match an opening bracket
(?: # A non capturing group
(?&str_double_quotes) # Recurse/use the str_double_quotes pattern
| # Or
(?&str_single_quotes) # Recurse/use the str_single_quotes pattern
| # Or
[^()] # Anything not a bracket
| # Or
(?&brackets) # Recurse the bracket pattern
)*
\)
)
) # End of definitions
# Let's start matching for real now:
_n? # Match _ or _n
\s* # Optional white spaces
(?P<results>(?&brackets)) # Recurse/use the brackets pattern and put it in the results group
~sx
regex;
$argumentsPattern = <<<'regex'
~ # Delimiter
(?(DEFINE) # Start of definitions
(?P<str_double_quotes>
(?<!\\) # Not escaped
" # Match a double quote
(?: # Non-capturing group
[^\\] # Match anything not a backslash
| # Or
\\. # Match a backslash and a single character (ie: an escaped character)
)*? # Repeat the non-capturing group zero or more times, ungreedy/lazy
" # Match the ending double quote
)
(?P<str_single_quotes>
(?<!\\) # Not escaped
' # Match a single quote
(?: # Non-capturing group
[^\\] # Match anything not a backslash
| # Or
\\. # Match a backslash and a single character (ie: an escaped character)
)*? # Repeat the non-capturing group zero or more times, ungreedy/lazy
' # Match the ending single quote
)
(?P<array>
Array\s*
(?&brackets)
)
(?P<variable>
[^\s,()]+ # I don't know the exact grammar for a variable in ECMAScript
)
(?P<brackets>
\( # Match an opening bracket
(?: # A non capturing group
(?&str_double_quotes) # Recurse/use the str_double_quotes pattern
| # Or
(?&str_single_quotes) # Recurse/use the str_single_quotes pattern
| # Or
(?&array) # Recurse/use the array pattern
| # Or
(?&variable) # Recurse/use the array pattern
| # Or
[^()] # Anything not a bracket
| # Or
(?&brackets) # Recurse the bracket pattern
)*
\)
)
) # End of definitions
# Let's start matching for real now:
(?&array)
|
(?&str_double_quotes)
|
(?&str_single_quotes)
|
(?&variable)
~six
regex;
$input = <<<'input'
_ ("foo") // want "foo"
_n("bar", "baz", 42); // want "bar", "baz", 42
_n(domain, "bux", var); // want domain, "bux", var
_( "one (optional)" ); // want "one (optional)"
apples === 0 ? _( "No apples" ) : _n("%1 apple", "%1 apples", apples) // could have on the same line two calls..
// misleading cases
_n("foo (")
_n("foo (\)", 'foo)', aa)
_n( Array(1, 2, 3), Array(")", '(') );
_n(function(foo){return foo*2;}); // Is this even valid?
_n (); // Empty
_ (
"Foo",
'Bar',
Array(
"wow",
"much",
'whitespaces'
),
multiline
); // PCRE is awesome
input;
if(preg_match_all($functionPattern, $input, $m)){
$filtered = preg_replace(
'~ # Delimiter
^ # Assert begin of string
\( # Match an opening bracket
\s* # Match optional whitespaces
| # Or
\s* # Match optional whitespaces
\) # Match a closing bracket
$ # Assert end of string
~x', // Regex
'', // Replace with nothing
$m['results'] // Subject
); // Getting rid of opening & closing brackets
// Part 3: extract arguments:
$parsedTree = array();
foreach($filtered as $arguments){ // Loop
if(preg_match_all($argumentsPattern, $arguments, $m)){ // If there's a match
$parsedTree[] = array(
'all_arguments' => $arguments,
'branches' => $m[0]
); // Add an array to our tree and fill it
}else{
$parsedTree[] = array(
'all_arguments' => $arguments,
'branches' => array()
); // Add an array with empty branches
}
}
print_r($parsedTree); // Let's see the results;
}else{
echo 'no matches';
}
您可能想要创建一个递归函数来生成完整的树。 See this answer
您可能会注意到function(){}
部分未正确解析。我会把它作为读者的练习:))
答案 1 :(得分:1)
答案 2 :(得分:0)
答案 3 :(得分:0)
\(( |"(\\"|[^"])*"|'(\\'|[^'])*'|[^)"'])*?\)
这应该在一对括号之间得到任何东西,忽略引号中的括号。 说明:
\( // Literal open paren
(
| //Space or
"(\\"|[^"])*"| //Anything between two double quotes, including escaped quotes, or
'(\\'|[^'])*'| //Anything between two single quotes, including escaped quotes, or
[^)"'] //Any character that isn't a quote or close paren
)*? // All that, as many times as necessary
\) // Literal close paren
无论你如何切片,正则表达式都会导致问题。它们难以阅读,难以维护且效率极低。我不熟悉gettext,但也许你可以使用for循环?
// This is just pseudocode. A loop like this can be more readable, maintainable, and predictable than a regular expression.
for(int i = 0; i < input.length; i++) {
// Ignoring anything that isn't an opening paren
if(input[i] == '(') {
String capturedText = "";
// Loop until a close paren is reached, or an EOF is reached
for(; input[i] != ')' && i < input.length; i++) {
if(input[i] == '"') {
// Loop until an unescaped close quote is reached, or an EOF is reached
for(; (input[i] != '"' || input[i - 1] == '\\') && i < input.length; i++) {
capturedText += input[i];
}
}
if(input[i] == "'") {
// Loop until an unescaped close quote is reached, or an EOF is reached
for(; (input[i] != "'" || input[i - 1] == '\\') && i < input.length; i++) {
capturedText += input[i];
}
}
capturedText += input[i];
}
capture(capturedText);
}
}
注意:我没有介绍如何确定它是函数还是仅仅是分组符号。 (即,这将匹配a = (b * c)
)。这很复杂,详见here。随着您的代码变得越来越准确,您越来越接近编写自己的javascript解析器。如果您需要这种准确性,您可能需要查看实际javascript解析器的源代码。
答案 4 :(得分:0)
一点代码(你可以在http://writecodeonline.com/php/测试这个PHP代码来检查):
$string = '_("foo")
_n("bar", "baz", 42);
_n(domain, "bux", var);
_( "one (optional)" );
apples === 0 ? _( "No apples" ) : _n("%1 apple", "%1 apples", apples)';
preg_match_all('/(?<=(_\()|(_n\())[\w", ()%]+(?=\))/i', $string, $matches);
foreach($matches[0] as $test){
$opArr = explode(',', $test);
foreach($opArr as $test2){
echo trim($test2) . "\n";
}
}
您可以在此处查看初始模式及其工作原理:http://regex101.com/r/fR7eU2/1
输出是:
"foo"
"bar"
"baz"
42
domain
"bux"
var
"one (optional)"
"No apples"
"%1 apple"
"%1 apples"
apples
答案 5 :(得分:-1)
我们可以分两步完成:
1)捕获_n(或_(方法调用
)的所有函数参数(?:_\(|_n\()(?:[^()]*\([^()]*\))*[^()]*\)
参见演示。
http://regex101.com/r/oE6jJ1/13
2)只抓住那些串状的
"([^"]*)"|(?:\(|,)\s*([^"),]*)(?=,|\))
参见演示。