On Fri, 3 Jul 2009, Richard Neill wrote: > > > Description: > > > Bash allows escape characters to be embedded by using the $'\n' > > > syntax. However, unlike all other $variables, > > > this doesn't work with embedded newlines. I think it should. > > > > > > Repeat-By: > > > X="a$'\n'b c" > > > echo "$X" > > > > > > expect to see: > > > a > > > b c > > > > > > actually see: > > > a$'\n'b c > > > > > > > > > Fix: > > > $'\n' should be expanded within double-quotes, like other variables > > > are. Otherwise, please correct the man-page to make it clearer. > > > > $'\n' is not a variable. As the man page says: > > > > Words of the form $'string' are treated specially. > > > > Note "Words". Inside double quotes, $'\n' is not a word. > > I agree that this is technically correct. However, it violates the principle > of least-surprise, which is that, in bash, the $ symbol always expands the > value of the thing after it, (with the exceptions of > '$' and \$ .) > > (On re-reading the man-page, I agree that the documentation is consistent with > your explanation; though it still appears more likely to imply mine) > > > > If this is a feature, not a bug, then is there a better way to include > > > newlines in a variable-assignment? > > > The syntax X="a"$'\n'"b c" will do it, but that is really really > > > ugly. > > > > X=$'a\nb c' > > > > This is still a missing feature: how to embed newlines in double-quoted bash > string assignment: > > For example, if I want to write: > > EMAIL_BODY="Dear $NAME,$'\n\n'Here are the log-files for > $(date)$'\n\n'Regards,$'\n\n'$SENDER" > > then this doesn't work. There are ways around it, such as: > - building up the string in pieces or > - EMAIL_BODY=$(echo -e "$EMAIL_BODY") > > but it's really ugly to do.
You can include literal newlines inside double quotes: EMAIL_BODY="Dear $NAME, Here are the log-files for $(date) Regards, $SENDER" You can assign a newline to a variable and include that: NL=$'\n' string="This is a$NLmulti-line$NLstring" There are other ways as well. > As I imagine that nobody uses the current $'\n' inside double-quotes, may I > request this as a functionality change? -- Chris F.A. Johnson, webmaster <http://woodbine-gerrard.com> =================================================================== Author: Shell Scripting Recipes: A Problem-Solution Approach (2005, Apress)
