perlsh - one-line perl evaluator with line editing function and
variable name completion function
This program reads input a line, and evaluates it by perl
interpreter, and prints the result. If the result is a list value then each
value of the list is printed line by line. This program can be used as a
very strong calculator which has whole perl functions.
This is a sample program Term::ReadLine::Gnu module. When you
input a line, the line editing function of GNU Readline Library is
available. Perl symbol name completion function is also available.
Before invoking, this program reads ~/.perlshrc and
evaluates the content of the file.
When this program is terminated, the content of the history buffer
is saved in a file ~/.perlsh_history, and it is read at next
invoking.
You can customize the behavior of
"perlsh" by setting following variables in
~/.perlshrc;
- $PerlSh::PS1
- The primary prompt string. The following backslash-escaped special
characters can be used.
\h: host name
\u: user name
\w: package name
\!: history number
The default value is `"\w[\!]$
"'.
- $PerlSh::PS2
- The secondary prompt string. The default value is
`"> "'.
- $PerlSh::HISTFILE
- The name of the file to which the command history is saved. The default
value is "~/.perlsh_history".
- $PerlSh::HISTSIZE
- If not "undef", this is the maximum
number of commands to remember in the history. The default value is
256.
- $PerlSh::STRICT
- If true, restrict unsafe constructs. See "use
strict" in perl man page. The default value is 0;
- ~/.perlshrc
- This file is eval-ed at initialization. If a subroutine
"afterinit" is defined in this file, it
will be eval-ed after initialization. Here is a sample.
# -*- mode: perl -*-
# decimal to hexa
sub h { map { sprintf("0x%x", $_ ) } @_;}
sub tk {
$t->tkRunning(1);
use Tk;
$mw = MainWindow->new();
}
# for debugging Term::ReadLine::Gnu
sub afterinit {
*t = \$PerlSh::term;
*a = \$PerlSh::attribs;
}
- ~/.perlsh_history
- ~/.inputrc
- A initialization file for the GNU Readline Library. Refer its manual for
details.
Term::ReadLine::Gnu
<http://search.cpan.org/dist/Term-ReadLine-Gnu/>
GNU Readline Library
<https://tiswww.cwru.edu/php/chet/readline/rltop.html>
Hiroo Hayashi <hiroo.hayashi@computer.org>