You might think, Boy, is there a context expensive grammar out there? What's the opposite of free?

These grammars that we've been introducing describe something new context free languages.

I am just gonna pause for a moment to let you think about that.

like HTML or SQL, the language of database queries.

The set of languages that can be described by re write rules or grammers like this are called context free languages.

But that's an example of an application that also uses this sort of linguistic analysis perhaps a little less related to context free grammars but still in the same vein.

It relates grammars to parsing, which is one of the concepts in this class.

Finite State Machines, adding a lexer that follows them automatically,

But if right above it I've written X 0, then we'd get a different answer.

It handles LL. It handles LR. It handles LALR.

That line above it is the context.

Y has the value of 2.

We'll talk about it in a lot of different contexts.

It depends on the context.

This branch of the family is all about representation.

So in lecture, we spent a lot of time learning about context free grammars and languages.

Actually, they're both just concise notations for specifying possibly infinite sets of strings.

Well, because, sentences are more interesting.

... the misspelled word shown in context...

These are just the ESPN SportsCenter version of the game.

Sometimes this statement is true, and sometimes it's not.

A context free grammar can capture the language a N and b N, where N is the same.

Another common story or storyline is the claim that we have to get tough .

Here I've written down four claims.

The brain is recording all information and driving all change in temporal context.

In theory, you could compose it over here as well.

They're the actual input that we're trying to match.

The input doesn't really have to be meaningful.

These are both infinite, infinite grammars.

Perhaps a stealth thing.

unparsed entity reference in wrong context

This is called being lazy, and it's a phenomenal virtue when you're writing programs.

In most interpreters, this is a problem.

That's an excellent question.

This is always true because we have our Pac Man diagram here, and also because you can take any regular language and represent it with a context free grammar.

They specify sets of strings, and they can be implemented under the hood with finite state machines.

In particular, it's a set of strings that can be represented by a finite state machine or a regular expression.

Build the system so that anybody can contribute at any amount.

But the question I wanna pose to you. And I, I don't have a slide after this one.

All right. So, it's another one of these puzzle like questions.

That's much more important than knowing the particular syntax for any language.

Units 3 and 4 were relatively abstract to some degree, intentionally so.

We need to know where we came from in order to know where we're going.

All right. Now that you've gone to the hard work of defining all of those procedures,

These days I think your time, the human's time, is more important than the computers.