22 Jun
2006
22 Jun
'06
8:08 p.m.
Christian Corti wrote:
On Wed, 21 Jun 2006, Don Y wrote:
Yes, sorry, I misremembered: ::= is the syntax for BNF's
introduced in the '68 report.
the capabilities of machines available at those
times. Though
I suspect some was just the author(s) taking poetic liberties
(e.g., Algol's ::= )
Algol's syntax constists of symbols like '<-' ';' and so on. If
you read
e.g. the book from the Alcor group you will see that they tell you, in
case that there are no '<-' etc. you may use more primitive symbols to
represent them, e.g.
':=' = '<-'
'.,' = ';'
'..' = ':'
'.(' = '['
'.)' = ']'
and so on.
Now think if you want to write '<-' and don't even have a ':' ...
Right,
you have to write '..=' In Pascal, e.g., you can write '(*' and
'*)' instead of '{' and '}' if
you don't have curly brackets.
And in C you can use the pre-preprocessor trigraphs, etc.