Escape double quotes in parameter

Another way to escape quotes (though probably not preferable), which I've found used in certain places is to use multiple double-quotes. For the purpose of making other people's code legible, I'll explain.

Here's a set of basic rules:

  1. When not wrapped in double-quoted groups, spaces separate parameters:
    program param1 param2 param 3 will pass four parameters to program.exe:
         param1, param2, param, and 3.
  2. A double-quoted group ignores spaces as value separators when passing parameters to programs:
    program one two "three and more" will pass three parameters to program.exe:
         one, two, and three and more.
    3. Now to explain some of the confusion:
  3. Double-quoted groups that appear directly adjacent to text not wrapped with double-quotes join into one parameter:
    hello"to the entire"world acts as one parameter: helloto the entireworld.
    4. Note: The previous rule does NOT imply that two double-quoted groups can appear directly adjacent to one another.
  4. Any double-quote directly following a closing quote is treated as (or as part of) plain unwrapped text that is adjacent to the double-quoted group, but only one double-quote:
    "Tim says, ""Hi!""" will act as one parameter: Tim says, "Hi!"

Thus there are three different types of double-quotes: quotes that open, quotes that close, and quotes that act as plain-text.
Here's the breakdown of that last confusing line:

"   open double-quote group
T   inside ""s
i   inside ""s
m   inside ""s
    inside ""s - space doesn't separate
s   inside ""s
a   inside ""s
y   inside ""s
s   inside ""s
,   inside ""s
    inside ""s - space doesn't separate
"   close double-quoted group
"   quote directly follows closer - acts as plain unwrapped text: "
H   outside ""s - gets joined to previous adjacent group
i   outside ""s - ...
!   outside ""s - ...
"   open double-quote group
"   close double-quote group
"   quote directly follows closer - acts as plain unwrapped text: "

Thus, the text effectively joins four groups of characters (one with nothing, however):
Tim says,  is the first, wrapped to escape the spaces
"Hi! is the second, not wrapped (there are no spaces)
 is the third, a double-quote group wrapping nothing
" is the fourth, the unwrapped close quote.

As you can see, the double-quote group wrapping nothing is still necessary since, without it, the following double-quote would open up a double-quoted group instead of acting as plain-text.

From this, it should be recognizable that therefore, inside and outside quotes, three double-quotes act as a plain-text unescaped double-quote:

"Tim said to him, """What's been happening lately?""""

will print Tim said to him, "What's been happening lately?" as expected. Therefore, three quotes can always be reliably used as an escape.
However, in understanding it, you may note that the four quotes at the end can be reduced to a mere two since it technically is adding another unnecessary empty double-quoted group.

Here are a few examples to close it off:

program a b                       REM sends (a) and (b)
program """a"""                   REM sends ("a")
program """a b"""                 REM sends ("a) and (b")
program """"Hello,""" Mike said." REM sends ("Hello," Mike said.)
program ""a""b""c""d""            REM sends (abcd) since the "" groups wrap nothing
program "hello to """quotes""     REM sends (hello to "quotes")
program """"hello world""         REM sends ("hello world")
program """hello" world""         REM sends ("hello world")
program """hello "world""         REM sends ("hello) and (world")
program "hello ""world"""         REM sends (hello "world")
program "hello """world""         REM sends (hello "world")

Final note: I did not read any of this from any tutorial - I came up with all of it by experimenting. Therefore, my explanation may not be true internally. Nonetheless all the examples above evaluate as given, thus validating (but not proving) my theory.

I tested this on Windows 7, 64bit using only *.exe calls with parameter passing (not *.bat, but I would suppose it works the same).


I cannot quickly reproduce the symptoms: if I try myscript '"test"' with a batch file myscript.bat containing just @echo.%1 or even @echo.%~1, I get all quotes: '"test"'

Perhaps you can try the escape character ^ like this: myscript '^"test^"'?

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