perl 3.0 patch #22 patch #19, continued

[p5sagit/p5-mst-13.2.git] / perl.man.1

diff --git a/perl.man.1 b/perl.man.1
index ec50d5f..69f373f 100644 (file)
--- a/perl.man.1
+++ b/perl.man.1
@@ -1,7 +1,15 @@
 .rn '' }`
-''' $Header: perl.man.1,v 3.0.1.3 90/02/28 17:54:32 lwall Locked $
+''' $Header: perl_man.1,v 3.0.1.5 90/03/27 16:14:37 lwall Locked $
 ''' 
 ''' $Log:      perl.man.1,v $
+''' Revision 3.0.1.5  90/03/27  16:14:37  lwall
+''' patch16: .. now works using magical string increment
+''' 
+''' Revision 3.0.1.4  90/03/12  16:44:33  lwall
+''' patch13: (LIST,) now legal
+''' patch13: improved LIST documentation
+''' patch13: example of if-elsif switch was wrong  
+''' 
 ''' Revision 3.0.1.3  90/02/28  17:54:32  lwall
 ''' patch9: @array in scalar context now returns length of array
 ''' patch9: in manual, example of open and ?: was backwards
@@ -630,7 +638,12 @@ bar
 
 .fi
 Array literals are denoted by separating individual values by commas, and
-enclosing the list in parentheses.
+enclosing the list in parentheses:
+.nf
+
+       (LIST)
+
+.fi
 In a context not requiring an array value, the value of the array literal
 is the value of the final element, as in the C comma operator.
 For example,
@@ -645,6 +658,46 @@ assigns the entire array value to array foo, but
 
 .fi
 assigns the value of variable bar to variable foo.
+Note that the value of an actual array in a scalar context is the length
+of the array; the following assigns to $foo the value 3:
+.nf
+
+.ne 2
+    @foo = (\'cc\', \'\-E\', $bar);
+    $foo = @foo;               # $foo gets 3
+
+.fi
+You may have an optional comma before the closing parenthesis of an
+array literal, so that you can say:
+.nf
+
+    @foo = (
+       1,
+       2,
+       3,
+    );
+
+.fi
+When a LIST is evaluated, each element of the list is evaluated in
+an array context, and the resulting array value is interpolated into LIST
+just as if each individual element were a member of LIST.  Thus arrays
+lose their identity in a LIST\*(--the list
+
+       (@foo,@bar,&SomeSub)
+
+contains all the elements of @foo followed by all the elements of @bar,
+followed by all the elements returned by the subroutine named SomeSub.
+.PP
+A list value may also be subscripted like a normal array.
+Examples:
+.nf
+
+       $time = (stat($file))[8];       # stat returns array value
+       $digit = ('a','b','c','d','e','f')[$digit-10];
+       return (pop(@foo),pop(@foo))[0];
+
+.fi
+.PP
 Array lists may be assigned to if and only if each element of the list
 is an lvalue:
 .nf
@@ -1079,11 +1132,11 @@ or even
 
 .ne 8
        if (/^abc/)
-               { $abc = 1; last foo; }
+               { $abc = 1; }
        elsif (/^def/)
-               { $def = 1; last foo; }
+               { $def = 1; }
        elsif (/^xyz/)
-               { $xyz = 1; last foo; }
+               { $xyz = 1; }
        else
                {$nothing = 1;}
 
@@ -1400,3 +1453,22 @@ as a string, preserving each character within its range, with carry:
 
 .fi
 The autodecrement is not magical.
+.PP
+The range operator (in an array context) makes use of the magical
+autoincrement algorithm if the minimum and maximum are strings.
+You can say
+
+       @alphabet = (\'A\' .. \'Z\');
+
+to get all the letters of the alphabet, or
+
+       $hexdigit = (0 .. 9, \'a\' .. \'f\')[$num & 15];
+
+to get a hexadecimal digit, or
+
+       @z2 = (\'01\' .. \'31\');  print @z2[$mday];
+
+to get dates with leading zeros.
+(If the final value specified is not in the sequence that the magical increment
+would produce, the sequence goes until the next value would be longer than
+the final value specified.)