Formal languages

Lexical grammar

In computer science, a lexical grammar is a formal grammar defining the syntax of tokens. The program is written using characters that are defined by the lexical structure of the language used. The character set is equivalent to the alphabet used by any written language. The lexical grammar lays down the rules governing how a character sequence is divided up into subsequences of characters, each part of which represents an individual token. This is frequently defined in terms of regular expressions. For instance, the lexical grammar for many programming languages specifies that a string literal starts with a " character and continues until a matching " is found (escaping makes this more complicated), that an identifier is an alphanumeric sequence (letters and digits, usually also allowing underscores, and disallowing initial digits), and that an integer literal is a sequence of digits. So in the following character sequence "abc" xyz1 23 the tokens are string, identifier and number (plus whitespace tokens) because the space character terminates the sequence of characters forming the identifier. Further, certain sequences are categorized as keywords – these generally have the same form as identifiers (usually alphabetical words), but are categorized separately; formally they have a different token type. (Wikipedia).

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SYN109 - Word Stores

This E-lecture first draws a distinction between dictionaries and lexicons and then discusses the role of the lexicon in linguistics. It shows how lexical entries are specified linguistically.

From playlist VLC206 - Morphology and Syntax

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SYN103 - Grammar (Overview)

There is a great deal of confusion about the term 'grammar'. Most people associate with it a book written about a language. In fact, there are various manifestations of this traditional term: presecriptive, descriptive and reference grammar. In theoretical linguistics, grammars are theory

From playlist VLC107 - Syntax: Part II

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CONCRETE NOUNS and ABSTRACT NOUNS - ENGLISH GRAMMAR

Concrete nouns are nouns that can be heard, tasted, smelled, touched, or seen. Abstract nouns are nouns that can be believed, felt emotionally, understood, learned, or known. LIKE AND SHARE THE VIDEO IF IT HELPED! Support me on Patreon: http://bit.ly/2EUdAl3 Visit our website: http://

From playlist English Grammar

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[Syntax] Nouns and Their Grammatical Properties

We introduce nouns and their grammatical properties, such as gender, class, number, nominative case, accusative case, genitive case. LIKE AND SHARE THE VIDEO IF IT HELPED! Visit our website: http://bit.ly/1zBPlvm Subscribe on YouTube: http://bit.ly/1vWiRxW Like us on Facebook: http://on.

From playlist Syntax

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Computational Semantics: How Computers Know what Words Mean [Lecture]

This is a single lecture from a course. If you you like the material and want more context (e.g., the lectures that came before), check out the whole course: https://boydgraber.org/teaching/CMSC_723/ (Including homeworks and reading.) Music: https://soundcloud.com/alvin-grissom-ii/review

From playlist Computational Linguistics I

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Introduction to Lexical Analyzer and Grammars | L 2 | Compiler Design | GATE CS #RavindrababuRaula

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From playlist Compiler Design

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Compiler Design lecture 1-- Introduction and various phases of compiler

Click for free access to Educator's best classes: : https://www.unacademy.com/a/Best-Classes-of-all-time-by-Vishvadeep-Gothi-CS.html For regular updates follow : https://unacademy.com/community/Q3ZGJY/ To purchase please click : https://unacademy.onelink.me/081J/zv9co3u1

From playlist Compiler Design

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SYN110 - Variants of Generative Grammar I

There are several problems for simple phrase structure grammars (PSG). In this first E-Lecture of a series of related videos, Prof. Handke discusses these problems and points out where and what adjustments have to be made to expand a simple PSG into a more elaborate version of a generative

From playlist VLC107 - Syntax: Part II

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SYN120 - The Verb in PDE, Part I

This first of a series of three E-Lectures discusses the notions verb, verb phrase and verb groups. It also includes the term predicate to arrive at a formal classification of these terms in PDE, which can be used for further analysis.

From playlist VLC201 - The Structure of English

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SYN109 - Lexical Insertion

Only very rarely do words occur in isolation. Rather, they are inserted into precisely defined syntactic contexts. This E-Lecture discusses the principles of lexical insertion from categorization to the definitin of the argument structure of lexemes.

From playlist VLC206 - Morphology and Syntax

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Lecture 6: Dependency Parsing

Lecture 6 covers dependency parsing which is the task of analyzing the syntactic dependency structure of a given input sentence S. The output of a dependency parser is a dependency tree where the words of the input sentence are connected by typed dependency relations. Key phrases: Depende

From playlist Lecture Collection | Natural Language Processing with Deep Learning (Winter 2017)

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NOUN PHRASES - ENGLISH GRAMMAR

We discuss noun phrases. Noun phrases consist of a head noun, proper name, or pronoun. Noun phrases can be modified by adjective phrases or other noun phrases. Noun phrases take determiners as specifiers. We also draw trees for noun phrase. you want to support the channel, hit the "JOIN"

From playlist English Grammar

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COMMON, PROPER, COUNT, and MASS NOUNS - ENGLISH GRAMMAR

We introduce common nouns, proper nouns, and some tests. Nouns are people, places, things, or abstract ideas. Nouns appear after determiners, quantifiers, or as the subject of a sentence. Nouns can be countable or uncountable/mass. LIKE AND SHARE THE VIDEO IF IT HELPED! Support me on P

From playlist English Grammar

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Lec 17 | MIT 6.035 Computer Language Engineering, Fall 2005

Instruction Scheduling (cont.) View the complete course: http://ocw.mit.edu/6-035F05 License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu

From playlist MIT 6.035 Computer Language Engineering, Fall 2005

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Phases of Compiler Design Practice Questions | CD | GATE CS | GATE 2022 | Ravindrababu Ravula

In this video Ravindrababu Ravula sir discussing on "Phases of Compiler Design Practice Questions". If you want to download the practice questions you can watch the free class on unacademy and below is the link on Unacademy platform. At the end of the video you will get download link in

From playlist Compiler Design

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Grammar: Who's or Whose?

In this video, you’ll learn more about when to use "whose" and "who's" correctly in American English. Visit https://www.gcflearnfree.org/grammar/whos-or-whose/1/ for our text-based lesson. We hope you enjoy!

From playlist Grammar

Related pages

String literal | Regular expression | Formal grammar