Directly use ${parameter#word} of sh(1) - plumb - Open certain URL patterns with an ad-hoc opener (plumber)
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       ---
 (DIR) changeset fbb643c5a08aa493f72da86a0c0f9f6907f7dfd7
 (DIR) parent 6c04d40595c8c7e761b956420dbb0565b097679a
 (HTM) Author: Leonardo Taccari <iamleot@gmail.com>
       Date:   Sat, 24 Mar 2018 21:36:01 
       
       Directly use ${parameter#word} of sh(1)
       
       Apart avoiding printf(1) and cut(1) now the arXiv id does not
       contain two extra `//' at the beginning.
       
       Diffstat:
        openers/arxiv |  2 +-
        1 files changed, 1 insertions(+), 1 deletions(-)
       ---
       diff -r 6c04d40595c8 -r fbb643c5a08a openers/arxiv
       --- a/openers/arxiv     Sat Mar 24 20:31:08 2018 +0100
       +++ b/openers/arxiv     Sat Mar 24 21:36:01 2018 +0100
       @@ -1,7 +1,7 @@
        #!/bin/sh
        
        for u in "$@"; do
       -       id="$(printf "%s\n" "$u" | cut -d : -f 2)"
       +       id="${u#*://}"
               pdfurl="https://arxiv.org/pdf/${id}.pdf"
               plumb "${pdfurl}"
        done