Re: Top 10 most common hard skills listed on resumes...

Bart <bc@freeuk.com> writes:

On 31/08/2024 23:10, Tim Rentsch wrote:
>

Bart <bc@freeuk.com> writes:

[...]

Given this:
>
    x + y = z;
    (x + y) = z;
>
My compiler produces the same AST for the LHS of '=' in both
cases.

>
To understand why they are different, try drawing parse trees
rather than abstract syntax trees.
>
https://en.wikipedia.org/wiki/Parse_tree

>
Yeah, the CST differs in retaining the parentheses.  But I can
already see that from the source code.
>
For normal compilation, that information is redundant.

The parse trees are different in a lot more ways than whether
one keeps parentheses.  But the point is to compare the parse
tree for x + y = z to the abstract syntax tree for x + y = z.
Among other things, the input x + y = z doesn't even have a
parse tree;  the rules governing the formation of parse trees
don't allow any parse tree matching that entire input.