Comments
Comments in any programming language that supports them are a way to tell a compiler or an interpreter to ignore certain parts of a code or script and not execcute them.
Blade supports like most languages a Single Line Comment and a Multi-line Comment (otherwise known as Block Comments).
Reference
Single line comments
A single line comment in Blade starts with an hash (#
) character and can appear anywhere in a REPL session or a script except between two single ('
) or double ("
) quotation marks. A single line comment can start the entire line or be inserted later in a line.
%> # this is my first Blade single line comment
%> echo 'Not a #comment' # assigning x to 15
'Not a #comment'
%> # and I am just inserting the comment for fun
%> # echo 'Hello there!'
You can go ahead and try this lines out in the REPL. You'll see that only the second line has an effect and even that line was treated as if we never
wrote that assigning x to 15
part.
Also notice how the
#
within the single quotes ('
) was echoed to screen. Because within those quotes,#
does not interpret as a commet but rather as the hash that it is.
Multi-line (Block) comments
Somtimes, we want comments that span multiple lines. For example, we could want to insert a long textual description of what a piece of code does, what code is contained in the file or simple stop a long piece of code suspected to be causing bugs from running i.e. for debugging. In this scenarios and many alike, a multi-line or block comment is preferred.
You can create block comments as follows:
/*
This
is a comment
that spans
multiple or block
lines
*/
A multi-line/block comment starts with a /*
and ends with a */
.
One important thing to note is that block comments in Blade can be nested within one another. This support was added to allow commenting out a portion of code that when uncommented do not lead to uncommenting another code within it's path that would lead to unintended bugs.
/*
This is a block
/*
And this is the internal
block comment
*/
that contains,
another block comment
*/
It's important to known that while the REPL supports the block comment syntax, for now, it only supports writing a block comment on a single line. So in a REPL session, the above sample may fails. But you can definitely write something like:
%> /* A block comment */