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Re: Arithmetic pow results incorrect in arithmetic expansion.
From: |
Chet Ramey |
Subject: |
Re: Arithmetic pow results incorrect in arithmetic expansion. |
Date: |
Sun, 10 Jan 2021 14:14:35 -0500 |
User-agent: |
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 |
On 1/9/21 12:22 AM, Oğuz wrote:
Here's another trivial side effect of implementing
unary minus using binary minus:
$ echo $((16#-10))
-10
Since `-' is an operator, this is not unary minus. It's the same as
$(( 16# - 10 )), which bash before version 5.1 helpfully (or not) treats
identically to $(( 16#0 - 10 )). Bash-5.1 requires at least one digit
after the base specification, so this is a syntax error.
$ echo $((-16#10))
-16
This is unary minus applied to an integer constant.
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/