Using arrays in bash using strings to bash built-in true Post: 302614429

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Top Forums Shell Programming and Scripting Using arrays in bash using strings to bash built-in true Post 302614429 by Corona688 on Wednesday 28th of March 2012 01:26:41 PM

03-28-2012

Registered User

Quote:

Originally Posted by kristinu

How about ksh? Can I use associative arrays without worry about using them?

How about trying what I suggested? Did it work, or did it not?

Quote:

Can one do the following in bash?

Code:

false=0
true=1

BASH is not C. I don't see any point in doing this. It's not going to make your code simpler. All you're going to do is make your code more and more complicated and strange.

Learn a tiny bit more about shell programming instead. Use variables as they're intended to be used. It looks unfamiliar to you because it's not familiar. Once you recognize it, it won't be.

What I would do is use bash's -z flag to tell if variables are empty. That way, you don't have to set a thousand different empty variables to zero -- just leave them blank. If they're still blank after processing options, then nobody set them.

Code:

case "$1" in
--something)
        SOMETHING=1
        ;;
esac

if [ ! -z "$SOMETHING" ]
then
        echo "Someone passed the --something option"
fi

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DBIx::Class::Storage::DBI::NoBindVars(3pm)		User Contributed Perl Documentation		DBIx::Class::Storage::DBI::NoBindVars(3pm)

NAME

       DBIx::Class::Storage::DBI::NoBindVars - Sometime DBDs have poor to no support for bind variables

DESCRIPTION

       This class allows queries to work when the DBD or underlying library does not support the usual "?" placeholders, or at least doesn't
       support them very well, as is the case with DBD::Sybase

METHODS

   connect_info
       We can't cache very effectively without bind variables, so force the "disable_sth_caching" setting to be turned on when the connect info is
       set.

   _prep_for_execute
       Manually subs in the values for the usual "?" placeholders.

   interpolate_unquoted
       This method is called by "_prep_for_execute" for every column in order to determine if its value should be quoted or not. The arguments are
       the current column data type and the actual bind value. The return value is interpreted as: true - do not quote, false - do quote. You
       should override this in you Storage::DBI::<database> subclass, if your RDBMS does not like quotes around certain datatypes (e.g. Sybase and
       integer columns). The default method returns false, except for integer datatypes paired with values containing nothing but digits.

	WARNING!!!

	Always validate that the bind-value is valid for the current datatype.
	Otherwise you may very well open the door to SQL injection attacks.

   _prep_interpolated_value
       Given a datatype and the value to be inserted directly into a SQL query, returns the necessary string to represent that value (by e.g.
       adding a '$' sign)

AUTHORS

       See "CONTRIBUTORS" in DBIx::Class

LICENSE

       You may distribute this code under the same terms as Perl itself.

perl v5.14.2							    2011-05-10				DBIx::Class::Storage::DBI::NoBindVars(3pm)