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Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.5.0 Subject: Re: empty pipes To: zsh-users@zsh.org References: Content-language: en-US From: Ray Andrews In-reply-to: Content-type: text/plain; charset=UTF-8; format=flowed Content-transfer-encoding: 8bit X-Seq: 28525 Archived-At: X-Loop: zsh-users@zsh.org Errors-To: zsh-users-owner@zsh.org Precedence: list Precedence: bulk Sender: zsh-users-request@zsh.org X-no-archive: yes List-Id: List-Help: , List-Subscribe: , List-Unsubscribe: , List-Post: List-Owner: List-Archive: On 2022-12-11 19:40, Bart Schaefer wrote: > > That's why you have e.g. ${filter:-cat}. > Works.  Interesting that property 'cat' has of doing nothing there but politely moving the stream forward.  I don't recall ever using that construction before but the sweet thing is that I now know where to look for information about it.  Such wealth in the parameter expansions.  BTW thanks to our previous discussions concerning 'tree' I already know that my $filter must be an array quoted so as to present the correct invisible structure.  Easy once you understand the issue. BTW, do we have hard spaces? In certain columnizing situations an empty field is a problem so a field of hard spaces would hold the position while showing nothing.