tcl - grep 双引号内的单词

Question

如何在文件内的双引号内提取单词？例如

variable "xxx"

Answer 1

Reading a text file into Tcl is just this:

set fd [open $filename]
set data [read $fd]        ;# Now $data is the entire contents of the file
close $fd

To get the first quoted string (under some assumptions, notably a lack backslashed double quote characters inside the double quotes), use this:

if {[regexp {"([^""]*)"} $data -> substring]} {
    # We found one, it's now in $substring
}

(Doubling up the quote in the brackets is totally unnecessary — only one is needed — but it does mean that the highlighter does the right thing here.)

The simplest method of finding all the quoted strings is this:

foreach {- substring} [regexp -inline -all {"([^""]*)"} $data] {
    # One of the substrings is $substring at this point
}

Notice that I'm using the same regular expression in each case. Indeed, it's actually good practice to factor such REs (especially if repeatedly used) into a variable of their own so that you can “name” them.

---

Combining all that stuff above:

set FindQuoted {"([^""]*)"}

set fd [open $filename]
foreach {- substring} [regexp -inline -all $FindQuoted [read $fd]] {
    puts "I have found $substring for you"
}
close $fd

Answer 2

内部匹配

如果您只是在寻找正则表达式，那么您可以使用 TCL 的捕获组。例如：

set string {variable "xxx"}
regexp {"(.*)"} $string match group1
puts $group1

这将返回xxx，丢弃引号。

外部匹配

如果您想匹配文件中的数据而无需直接将文件读入 TCL，您也可以这样做。例如：

set match [exec sed {s/^variable "\(...\)"/\1/} /tmp/foo]

这将调用 sed 来查找您想要的匹配部分，并将它们分配给 TCL 变量以进行进一步处理。在此示例中，匹配变量设置xxx为如上，但操作的是外部文件而不是存储的字符串。

Answer 3

When you just want to find with grep all words in quotes in a file and do something with the words, you do something like this (in a shell):

grep -o '"[^"]*"' | while read word
do
   # do something with $word
   echo extracted: $word
done