On 11/29/2002 7:40 PM, Joseph Ryan wrote:
I belive it goes somthing like this:- References and Object stringification hasn't been defined.
All objects define a .AS_STRING method. This method is called to stringify the object. The builtin types have builtin .AS_STRINGs, the primitive types autopromote. All strinification thus follows the same logical model, even if the implementation doesn't.
The default .AS_STRING for Strings is obvious. Int and Num stringify to a decimal number (using the e exponential form if it is shorter?).
Multi-leveled: The outer .AS_STRING calls it's members' .AS_STRINGs. Circular: I have no idea.- If References interpolate in some sort of readable way, how do multi-leveled references interpolate, and how do self-referring data structures interpolate?
Possibly misleading: Leads people to think that a string is an array of chars, like in C? (I don't think so, but new-to-perl people might. I'm being nitpicky.)A string is a literal value that represents a sequence of characters.
The base form for a non-interpolating string is the single-quoted
string: 'string'. However, non-interpolating strings can also be formed
with the q() operator. The q() operator allows strings to be made with
any non-space, non-letter, non-digit character as the delimeter instead
of '. In addition, if the starting delimeter is a part of a paired
set, such as (, [, <, or {, then the closing delimeter may be the
matching member of the set. In addition, the reverse holds true;
delimeters which are the tail end of a pair may use the starting item
as the closing delimeter.
It is also possible to embed an interpolating string within a non-
interpolating string by the use of the \qq{} construct. A string
inside a \qq{} constructs acts exactly as if it were an interpolated
string. Note that any end-brackets, "}", must be escaped within the
the \qq{} construct so that the parser can read it correctly.
I thought it was named <<foo bar baz>> or «foo bar baz» or qw(). (That middle one should be U+00AB and U+00BB, \N{LEFT-POINTING DOUBLE ANGLE QUOTATION MARK} and \N{RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK}. Additionaly, I'm fairly certian, the Unicode ops could be either direction. I think there was a reason for that, but I don't remember what.=head3 <>; expanding a string as a list.A set of braces is a special op that evaluates into the list of words contained, using whitespace as the delimeter. It is similar to qw() from perl5, and can be thought of as roughly equivalent to: C<< "STRING".split(' ') >>
\t tab
\U{9}
\n newline
\U{10}
\r return
\U{13}
\f form feed
\U{12}
\b backspace
\U{8}
\a alarm (bell)
\U{7}
\e escape
\U{27}
Is this true? We changed the numeric octal shorthand base to 0c777, so what sense does \o for octal charcters make? (Unfornatly, we can't use \c, since that's taken for control charcters.) IIRC, somebody had mentioned just getting rid of \o altogether. People don't think in octal.\b10 binary char \o33 octal char
Specificly, \x must be followed by exactly two hex digits, or do we DWIM with one (IE, if there is only one character in 0-9A-Fa-f after the \x, do we\x1b hex char
\x{263a} wide hex cha
\c[ control char
\N{name} named Unicode character
\Q{} Escape all characters that need escaping
within the current string (except "}")
Within an interpolated string, interpolation of expressions can be stopped by \Q.
(Which acts somewhat like a non-breaking space.)
The collected standard output of theStandard error is passed on to the standard error of the perl process? (Or should we leave it at "unaffected", and let the user guess what that means on their OS -- I'm betting I'm being unix-centric here -- OS<=9 has no concept of "standard error" -- or "standard output", for that matter... IIRC, again.)
command is returned; standard error is unaffected.
I don't think $/ still exists, at least as such. In fact, I think we should probably just say "returns an iterator on the standard output of the command", and leave it at that.In scalar context, it comes back as a single (potentially multi-line) string, or undef if the command failed. In list context, returns a list of lines (however you've defined lines with $/ or $INPUT_RECORD_SEPARATOR), or an empty list if the command failed.
I think we need a non-optional space to follow the << in the case of double-quotes to disambuilage with <<>> qw lists.# modified from perl5's perlop A line-oriented form of quoting is based on the shell "here-document" syntax. Following a << you specify a string to terminate the quoted material, and all lines following the current line down to the terminating string are the value of the item. The terminating string may be either an identifier (a word), or some quoted text. If quoted, the type of quotes you use determines the treatment of the text, just as in regular quoting. An unquoted identifier works like double quotes.
This should probably be a link to somthing defining exactly what whitespace is in perl. I suspect we should follow Unicode's defintion of whitespace -- possibly dissallowing the zero-width whitespace, for sanity reasons. Come to think of it, I think Unicode has both the concept of "whitespace" and of "word-sepperating characters", which aren't neccessarly the same -- zero-width non-breaking space is nonprinting, and doesn't wordbreak, but is whitespace!The terminating string must appear by itself, and any preceding or following whitespace on the terminating line is discarded.
I think this section is going to be very much different -- since the perl6 parser is going to be defined in perl6 regexes, it may just say "see anydelimiter.pl and quoted.pl".=head2 Gory Details of parsing quoted constructs
-=- James Mastros
