Vista - Use of matching subexpressions in "-replace" operator

09-09-2007

Someone, please clarify if so-called "matching subexpressions" can be used
in the replacement string of the PowerShell "-replace" operator? E.g.
something like

"20070909" -replace "(\d\d\d\d)(\d\d)(\d\d)","$1-$2-$3"

to yield "2007-09-09"?

The above statement actually returns "--" in PowerShell, since $1, $2, and
$3 apparently are undefined. I didn't expect this behaviour since "matching
subexpressions" are defined in .NET regular expressions and they seem to be
allowed in the search string of the -replace operator..

Audun.

09-09-2007

Yep

"20070909" -replace "(\d\d\d\d)(\d\d)(\d\d)",'$1-$2-$3'
2007-09-09

Shay
http://scriptolog.blogspot.com

Quote:

> Someone, please clarify if so-called "matching subexpressions" can be
> used in the replacement string of the PowerShell "-replace" operator?
> E.g. something like
>
> "20070909" -replace "(\d\d\d\d)(\d\d)(\d\d)","$1-$2-$3"
>
> to yield "2007-09-09"?
>
> The above statement actually returns "--" in PowerShell, since $1, $2,
> and $3 apparently are undefined. I didn't expect this behaviour since
> "matching subexpressions" are defined in .NET regular expressions and
> they seem to be allowed in the search string of the -replace
> operator..
>
> Audun.
>

09-09-2007

Use single quotes to avoid variable expansion:

"20070909" -replace "(\d\d\d\d)(\d\d)(\d\d)", '$1-$2-$3'

--
Kiron

09-09-2007

Thank you! Quite subtle error. The devil surely is in the details...

Audun

"Kiron" <Kiron@xxxxxx> wrote in message
news:umzZ%23Lx8HHA.5424@xxxxxx
Use single quotes to avoid variable expansion:

"20070909" -replace "(\d\d\d\d)(\d\d)(\d\d)", '$1-$2-$3'

--
Kiron

09-09-2007	#1 (permalink)
Audun Gjerken n/a posts	Use of matching subexpressions in "-replace" operator Someone, please clarify if so-called "matching subexpressions" can be used in the replacement string of the PowerShell "-replace" operator? E.g. something like "20070909" -replace "(\d\d\d\d)(\d\d)(\d\d)","$1-$2-$3" to yield "2007-09-09"? The above statement actually returns "--" in PowerShell, since $1, $2, and $3 apparently are undefined. I didn't expect this behaviour since "matching subexpressions" are defined in .NET regular expressions and they seem to be allowed in the search string of the -replace operator.. Audun.
My System Specs

09-09-2007	#2 (permalink)
Shay Levi n/a posts	Re: Use of matching subexpressions in "-replace" operator Yep "20070909" -replace "(\d\d\d\d)(\d\d)(\d\d)",'$1-$2-$3' 2007-09-09 Shay http://scriptolog.blogspot.com Quote: > Someone, please clarify if so-called "matching subexpressions" can be > used in the replacement string of the PowerShell "-replace" operator? > E.g. something like > > "20070909" -replace "(\d\d\d\d)(\d\d)(\d\d)","$1-$2-$3" > > to yield "2007-09-09"? > > The above statement actually returns "--" in PowerShell, since $1, $2, > and $3 apparently are undefined. I didn't expect this behaviour since > "matching subexpressions" are defined in .NET regular expressions and > they seem to be allowed in the search string of the -replace > operator.. > > Audun. >
My System Specs

09-09-2007	#3 (permalink)
Kiron n/a posts	Re: Use of matching subexpressions in "-replace" operator Use single quotes to avoid variable expansion: "20070909" -replace "(\d\d\d\d)(\d\d)(\d\d)", '$1-$2-$3' -- Kiron
My System Specs

09-09-2007	#4 (permalink)
Audun Gjerken n/a posts	Re: Use of matching subexpressions in "-replace" operator Thank you! Quite subtle error. The devil surely is in the details... Audun "Kiron" <Kiron@xxxxxx> wrote in message news:umzZ%23Lx8HHA.5424@xxxxxx Use single quotes to avoid variable expansion: "20070909" -replace "(\d\d\d\d)(\d\d)(\d\d)", '$1-$2-$3' -- Kiron
My System Specs

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