[Pharo-project] [ENH] Syntax extension for continuations

Igor Stasenko siguctua at gmail.com
Mon Nov 1 03:37:33 CET 2010


Out of curiosity, i tried to look how it would be hard to change
parser to support extended continuation syntax.
And it was quite simple, i had to change only single method!

A new syntax using double semicolon ';;' to indicate a continuation.

So, code like:

self foo ;; bar ;; zork

is equivalent to:

self foo bar zork

But when its going to binary, or keyword messages, it allows to write
more clean code,
because it not requires using parenthesis.

For instance:

(1/10) asFloat

with new syntax can be written as:

1/10 ;; asFloat

More complex example:

((self foo: bar) + 10 ) baz

can be written as

self foo: bar ;; + 10 ;; baz

Note, that it is same number of characters to type.. but is much more
clean, and less time expensive to code,
because when you coding, you usually type first message:

self foo: bar `

and then you realising that next message is binary and hence you need
to go back to beginning of line and put open paren there:

`( self foo: bar

then again, go to the end of message, and continue typing:

( self foo: bar ` ) + 10

` - is cursor position.

so, it is much more keystrokes & navigation than just typing two semicolons :)

P.S. don't burn me for my herecy, please :)

Best regards,
Igor Stasenko AKA sig.
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