From 23fdbc8400fc01e977753bc357ec9f4679a60290 Mon Sep 17 00:00:00 2001
From: Christian Neukirchen <chneukirchen@gmail.com>
Date: Sat, 13 Feb 2016 22:30:31 +0100
Subject: replace C prototype with Ruby script

---
 arr | 119 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 119 insertions(+)
 create mode 100755 arr

(limited to 'arr')

diff --git a/arr b/arr
new file mode 100755
index 0000000..8d5ba5a
--- /dev/null
+++ b/arr
@@ -0,0 +1,119 @@
+#!/usr/bin/env ruby
+# arr EXPR [FILES...] - (re)arrange and select fields on each line
+#
+# To the extent possible under law,
+# Christian Neukirchen <chneukirchen@gmail.com>
+# has waived all copyright and related or neighboring rights to this work.
+# http://creativecommons.org/publicdomain/zero/1.0/
+
+USAGE = <<'EOF'
+Usage: arr [-0] [-P|-p PADDING] EXPR [FILES...]
+  EXPR   ::= FIELDS (("|" CHAR | "*") FIELDS)*  # | split on char, * split bytes
+  FIELDS ::= "~"? FIELD ("," FIELD)*            # ~ negates
+  FIELD  ::= "-"? "\d"+                         # negative fields count from back
+           | ("-"? "\d"+)? ":" ("-"? "\d"+)?    # range ends default to 1:-1
+EOF
+
+require 'strscan'
+require 'optparse'
+
+def fmt(ss, d)
+  last_split = " "
+
+  loop {
+    fields = []
+    neg = false
+
+    begin
+      i = j = nil
+      neg = true  if ss.scan(/~/)
+      if ss.scan(/:|-?\d+/)
+        i = Integer(ss.matched) rescue 1
+        i = i < 0 ? d.size + i : i - 1
+        if ss.matched == ":" || ss.scan(/:/)
+          if ss.scan(/-?\d+/)
+            j = Integer(ss.matched)
+          else
+            j = -1
+          end
+          j = j < 0 ? d.size + j : j - 1
+
+          if j > i
+            fields.concat (i..j).to_a
+          else
+            fields.concat (j..i).to_a.reverse
+          end
+        else
+          fields << i
+        end
+      else
+        abort "parse error at #{ss.inspect}"
+      end
+    end while ss.scan(/,/)
+    
+    d = d.values_at(*if neg
+                       (0..d.size).to_a - fields
+                     else
+                       fields
+                     end)
+        
+    if ss.scan(/\|(.)/)
+      d = d.join(last_split)
+      last_split = ss[1]
+      d = d.split(last_split)
+    elsif ss.scan(/\*/)
+      d = d.join(last_split)
+      last_split = ""
+      d = d.split('')
+    else
+      break
+    end
+  }
+
+  unless ss.scan(/\}/)
+    abort "parse error at #{ss.inspect}"
+  end
+    
+  d.compact.join(last_split)
+end
+
+def fmt2(str, arr)
+  ss = StringScanner.new(str)
+  
+  r = ""
+
+  while ss.scan(/(.*?)%\{/)
+    r << ss[1]
+    r << fmt(ss, arr)
+  end
+
+  r << ss.rest
+end
+
+begin
+  params = ARGV.getopts('0Pp:')
+  nl = params["0"] ? "\0" : "\n"
+  padding = params["p"] || ""
+  padding = nil  if params["P"]
+  
+  expr = ARGV.shift  or raise OptionParser::MissingArgument, "no EXPR given"
+
+  ARGV << "-"  if ARGV.empty?
+
+  files = ARGV.map { |name|
+    if name == "-"
+      STDIN
+    else
+      File.open(name, "rb")
+    end
+  }
+
+  until files.all?(&:eof?)
+    lines = files.map { |f| f.gets(nl).chomp(nl) rescue padding }
+    break  if lines.include?(nil)
+    print fmt2(expr, lines), nl
+  end
+rescue OptionParser::ParseError
+  STDERR.puts $!
+  STDERR.puts USAGE
+end
-- 
cgit 1.4.1