Leading or trailing white space characters in file names

[Allen Smith]

Sorry. When I first saw his post, I was just skimming through new posts, and saw how long it was and put it off to look at later. Then, I forgot to come back later.

Me too. The scope of these changes transcended the original discussion, and I forgot to loop back around.

Roland did a lot of hard work here, and has good ideas for changes. Thanks Roland! However, I think we should table these new issues until resolving the immediate issue (just to keep us on a single topic; re-introduce them afterward):

• Line endings
  
• Comments/Meta rewrite
  

I suggest the following revised text, in which I hope I've capture the spirit of Roland's work while avoiding raising new issues. I want to make the leading whitespace issue explicit. While framing the discussion in terms of tokens is technically accurate, I think it makes the leading whitespace issue subtle enough to be accidentally overlooked.

Every line of the file contains one command. With few exceptions, every command is independent of other lines. The exceptions are the BFC meta-commands which modify the behaviour of one or more following command lines. There is no line length restriction. The whitespace characters allowed for keyword and parameter separation include spaces and tabs. Every command starts with a number, called a line type. The function and format of the line is determined by the line type.

Basic parsing / file content

An LDraw file consists of one command per line. There is no line length restriction. Each command consists of optional leading whitespace followed by whitespace-delimited tokens. Some commands also have trailing arbitrary data which may itself include internal whitespace; such data is not tokenized, but treated as single unit according to the command.

Whitespace is defined as one or more spaces (#32), tabs (#9), or combination thereof.

Lines may also be empty or consist only of whitespace. Such lines have no effect.

If a line is non-empty, the first token must be an integer from the list of valid Line Type numbers. This number dictates further parsing of tokens for that line. The parsing rules per linetype follow below.

Although not mandatory, it is recommended to not use leading whitespace before the linetype token on the fist line of a file. This to assist software in determining the character encoding of the file.

I am of the opinion to completely strike the disclaimer about first-line leading whitespace.

<file> is the filename of the sub-file referenced and must be a valid LDraw filename.

<file> is the filename of the sub-file referenced and must be a valid LDraw filename. Any leading and/or trailing whitespace must be ignored. Normal token separation is otherwise disabled for the filename value.