The document provides an overview of the Kotlin programming language, including:
- It is statically typed and compiles to JVM bytecode or JavaScript.
- It is intended for industrial use and prioritizes readability, simple abstractions, and performance.
- It is open source and has keywords, basic syntax, and rules for variable types similar to Java but less verbose.
Notation, Regular Expressions in Lexical Specification, Error Handling, Finite Automata State Graphs, Epsilon Moves, Deterministic and Non-Deterministic Automata, Table Implementation of a DFA
Finite Automata: Deterministic And Non-deterministic Finite Automaton (DFA)Mohammad Ilyas Malik
The term "Automata" is derived from the Greek word "αὐτόματα" which means "self-acting". An automaton (Automata in plural) is an abstract self-propelled computing device which follows a predetermined sequence of operations automatically.
Kotlin For Android - Properties (part 4 of 7)Gesh Markov
This presentation is part of a workshop series.
In this section you will learn about Java interop, synthetic and delegated properties, custom setters and getters, lateinit, nullable and non-null properties, and optional invocation
License:
This presentation is licensed under the Creative Commons, No Derivatives, Version 3.0 US: https://creativecommons.org/licenses/by-nd/3.0/us/legalcode
Notation, Regular Expressions in Lexical Specification, Error Handling, Finite Automata State Graphs, Epsilon Moves, Deterministic and Non-Deterministic Automata, Table Implementation of a DFA
Finite Automata: Deterministic And Non-deterministic Finite Automaton (DFA)Mohammad Ilyas Malik
The term "Automata" is derived from the Greek word "αὐτόματα" which means "self-acting". An automaton (Automata in plural) is an abstract self-propelled computing device which follows a predetermined sequence of operations automatically.
Kotlin For Android - Properties (part 4 of 7)Gesh Markov
This presentation is part of a workshop series.
In this section you will learn about Java interop, synthetic and delegated properties, custom setters and getters, lateinit, nullable and non-null properties, and optional invocation
License:
This presentation is licensed under the Creative Commons, No Derivatives, Version 3.0 US: https://creativecommons.org/licenses/by-nd/3.0/us/legalcode
recognizer for a language, Deterministic finite automata, Non-deterministic finite automata, conversion of NFA to DFA, Regular Expression to NFA, Thomsons Construction
Implicit conversions and implicit parameters are fundamental and unique features of Scala that are powerful at the same time. To use these features to their maximum potential, and do so with confidence, you have to understand the specifics of how Scala compiler’s implicits search works. I will cover this topic in details, including ways you can optimize the implicits search algorithm in your library.
The second part of my session will focus on IntelliJ IDEA and how to leverage your IDE for working with implicits. Among other helpful IDE features, I will show how to debug implicits in IntelliJ IDEA.
As examples we’ll take a look at a few Scala libraries, including Spray with its well-known Magnet pattern.
On top of that, during my talk I’ll show you a few new tips and tricks on how to be more efficient by using IntelliJ IDEA’s hidden gems when working with Scala. "
1. Python Presented By: Rajesh Kumar Guided By: Mr. Jaishankar Bhatt
2. Content Python Introduction Python Code Execution Python Comments & Indentation Variables Data Types Strings Collections (Arrays)
3. Python Introduction What is Python? Python is an interpreted, high-level, general-purpose programming language. Created by Guido van Rossum Released in 1991
4. Python Code Execution Source code extension is .py Byte code extension is .pyc (compiled python code) Python’s runtime execution model:
5. Comments •Creating a Comment: Ex: Comments starts with a # Output:
6. Comments •Multi Line Comments: Ex: or:
7. Python Indentation •Indentation refers to the spaces at the beginning of a code line. Ex1: Ex2:
8. Variables •Variables are containers for storing data values. Ex:
9. Data Types •Built-in Data Types
10. Getting the Data Type •You can get the data type of any object by using the type() method. Ex: Print the data type of the variable x: Output:
11. Setting the Data Type •In Python, the data type is set when you assign a value to a variable:
12. Strings •String literals in python are surrounded by either single quotation marks, or double quotation marks. •'hello' is the same as "hello". Ex:
13. Multiline Strings •You can assign a multiline string to a variable by using three quotes Ex: Output:
14. Slicing •You can return a range of characters by using the slice syntax. Ex:Get the characters from position 2 to position 5. Output:
15. String Methods Method Description len() Returns the length of a string. lower() Returns the string in lower case. upper() Returns the string in upper case. count() Returns the number of times a specified value appears in the string.
16. Collections (Arrays) •There are four collection data types in the Python programming language. Types: 1. List 2. Tuple 3. Set 4. Dictionary
17. Python Lists •A list is a collection which is ordered and changeable. In Python lists are written with square brackets. Ex: Create a List: Output:
18. Python Tuples •A tuple is a collection which is ordered and unchangeable. In Python tuples are written with round brackets. Ex: Create a Tuple: Output:
19. Python Sets •A set is a collection which is unordered and unindexed. In Python sets are written with curly brackets. Ex: Create a Set:
20. Python Dictionaries •A dictionary is a collection which is unordered, changeable and indexed. In Python dictionaries are written with curly brackets. Ex: Create a Dictionary:
21. Conclusion Python is a great option, whether you are a beginning programmer looking to learn the basics, an experienced programmer designing a large application, or anywhere in between. The basics of Python are easily grasped, and yet its capabilities are vast.
22. Reference https://www.udemy.com/course/learn- programming-with-python https://www.w3schools.com/python/default.asp
recognizer for a language, Deterministic finite automata, Non-deterministic finite automata, conversion of NFA to DFA, Regular Expression to NFA, Thomsons Construction
Implicit conversions and implicit parameters are fundamental and unique features of Scala that are powerful at the same time. To use these features to their maximum potential, and do so with confidence, you have to understand the specifics of how Scala compiler’s implicits search works. I will cover this topic in details, including ways you can optimize the implicits search algorithm in your library.
The second part of my session will focus on IntelliJ IDEA and how to leverage your IDE for working with implicits. Among other helpful IDE features, I will show how to debug implicits in IntelliJ IDEA.
As examples we’ll take a look at a few Scala libraries, including Spray with its well-known Magnet pattern.
On top of that, during my talk I’ll show you a few new tips and tricks on how to be more efficient by using IntelliJ IDEA’s hidden gems when working with Scala. "
1. Python Presented By: Rajesh Kumar Guided By: Mr. Jaishankar Bhatt
2. Content Python Introduction Python Code Execution Python Comments & Indentation Variables Data Types Strings Collections (Arrays)
3. Python Introduction What is Python? Python is an interpreted, high-level, general-purpose programming language. Created by Guido van Rossum Released in 1991
4. Python Code Execution Source code extension is .py Byte code extension is .pyc (compiled python code) Python’s runtime execution model:
5. Comments •Creating a Comment: Ex: Comments starts with a # Output:
6. Comments •Multi Line Comments: Ex: or:
7. Python Indentation •Indentation refers to the spaces at the beginning of a code line. Ex1: Ex2:
8. Variables •Variables are containers for storing data values. Ex:
9. Data Types •Built-in Data Types
10. Getting the Data Type •You can get the data type of any object by using the type() method. Ex: Print the data type of the variable x: Output:
11. Setting the Data Type •In Python, the data type is set when you assign a value to a variable:
12. Strings •String literals in python are surrounded by either single quotation marks, or double quotation marks. •'hello' is the same as "hello". Ex:
13. Multiline Strings •You can assign a multiline string to a variable by using three quotes Ex: Output:
14. Slicing •You can return a range of characters by using the slice syntax. Ex:Get the characters from position 2 to position 5. Output:
15. String Methods Method Description len() Returns the length of a string. lower() Returns the string in lower case. upper() Returns the string in upper case. count() Returns the number of times a specified value appears in the string.
16. Collections (Arrays) •There are four collection data types in the Python programming language. Types: 1. List 2. Tuple 3. Set 4. Dictionary
17. Python Lists •A list is a collection which is ordered and changeable. In Python lists are written with square brackets. Ex: Create a List: Output:
18. Python Tuples •A tuple is a collection which is ordered and unchangeable. In Python tuples are written with round brackets. Ex: Create a Tuple: Output:
19. Python Sets •A set is a collection which is unordered and unindexed. In Python sets are written with curly brackets. Ex: Create a Set:
20. Python Dictionaries •A dictionary is a collection which is unordered, changeable and indexed. In Python dictionaries are written with curly brackets. Ex: Create a Dictionary:
21. Conclusion Python is a great option, whether you are a beginning programmer looking to learn the basics, an experienced programmer designing a large application, or anywhere in between. The basics of Python are easily grasped, and yet its capabilities are vast.
22. Reference https://www.udemy.com/course/learn- programming-with-python https://www.w3schools.com/python/default.asp
In this PDF you can learn about Kotlin Basic as well as Intermediate part. As also you can develop the android apps and publish in a google play store.
This presentation comes with many additional notes (pdf): http://de.slideshare.net/nicolayludwig/2-cpp-imperative-programming-38499061
Check out these exercises: http://de.slideshare.net/nicolayludwig/2-cpp-imperative-programmingexercises
- Imperative Programming
- Style and Conventions
- Constants
- Fundamental Types
- Console Basics
- Operators, Precedence, Associativity and Evaluation Order
- Control Structures and Blocks
A File is a collection of data stored in the secondary memory. So far data wa...bhargavi804095
A File is a collection of data stored in the secondary memory. So far data was entered into the programs through the keyboard. So Files are used for storing information that can be processed by the programs. Files are not only used for storing the data, programs are also stored in files. In order to use files, we have to learn file input and output operations. That is, how data is read and how to write into a file. A Stream is the important concept in C. The Stream is a common, logical interface to the various devices that comprise the computer. So a Stream is a logical interface to a file. There are two types of Streams, Text Stream and Binary Stream. A Text File can be thought of as a stream of characters that can be processed sequentially. It can only be processed in the forward direction.
Introduction to Koltin for Android Part I Atif AbbAsi
Welcome to Android Basics in Kotlin! In this course, you'll learn the basics of building Android apps with the Kotlin programming language. Along the way, you'll develop a collection of apps to start your journey as an Android developer.
Check out these exercises: http://de.slideshare.net/nicolayludwig/2-cpp-imperative-programmingexercises
- Imperative Programming
- Style and Conventions
- Constants
- Fundamental Types
- Console Basics
- Operators, Precedence, Associativity and Evaluation Order
- Control Structures and Blocks
Brief and overall introduction to Artificial Neural Network (ANN).
-history of ANN
-learning technique (backpropagation)
-Generations of Neural net from 1st to 3rd
Prosigns: Transforming Business with Tailored Technology SolutionsProsigns
Unlocking Business Potential: Tailored Technology Solutions by Prosigns
Discover how Prosigns, a leading technology solutions provider, partners with businesses to drive innovation and success. Our presentation showcases our comprehensive range of services, including custom software development, web and mobile app development, AI & ML solutions, blockchain integration, DevOps services, and Microsoft Dynamics 365 support.
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Microsoft Dynamics 365 Support: Prosigns provides comprehensive support and maintenance services for Microsoft Dynamics 365, ensuring your system is always up-to-date, secure, and running smoothly.
Learn how our collaborative approach and dedication to excellence help businesses achieve their goals and stay ahead in today's digital landscape. From concept to deployment, Prosigns is your trusted partner for transforming ideas into reality and unlocking the full potential of your business.
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May Marketo Masterclass, London MUG May 22 2024.pdfAdele Miller
Can't make Adobe Summit in Vegas? No sweat because the EMEA Marketo Engage Champions are coming to London to share their Summit sessions, insights and more!
This is a MUG with a twist you don't want to miss.
SOCRadar Research Team: Latest Activities of IntelBrokerSOCRadar
The European Union Agency for Law Enforcement Cooperation (Europol) has suffered an alleged data breach after a notorious threat actor claimed to have exfiltrated data from its systems. Infamous data leaker IntelBroker posted on the even more infamous BreachForums hacking forum, saying that Europol suffered a data breach this month.
The alleged breach affected Europol agencies CCSE, EC3, Europol Platform for Experts, Law Enforcement Forum, and SIRIUS. Infiltration of these entities can disrupt ongoing investigations and compromise sensitive intelligence shared among international law enforcement agencies.
However, this is neither the first nor the last activity of IntekBroker. We have compiled for you what happened in the last few days. To track such hacker activities on dark web sources like hacker forums, private Telegram channels, and other hidden platforms where cyber threats often originate, you can check SOCRadar’s Dark Web News.
Stay Informed on Threat Actors’ Activity on the Dark Web with SOCRadar!
Enhancing Research Orchestration Capabilities at ORNL.pdfGlobus
Cross-facility research orchestration comes with ever-changing constraints regarding the availability and suitability of various compute and data resources. In short, a flexible data and processing fabric is needed to enable the dynamic redirection of data and compute tasks throughout the lifecycle of an experiment. In this talk, we illustrate how we easily leveraged Globus services to instrument the ACE research testbed at the Oak Ridge Leadership Computing Facility with flexible data and task orchestration capabilities.
Globus Compute wth IRI Workflows - GlobusWorld 2024Globus
As part of the DOE Integrated Research Infrastructure (IRI) program, NERSC at Lawrence Berkeley National Lab and ALCF at Argonne National Lab are working closely with General Atomics on accelerating the computing requirements of the DIII-D experiment. As part of the work the team is investigating ways to speedup the time to solution for many different parts of the DIII-D workflow including how they run jobs on HPC systems. One of these routes is looking at Globus Compute as a way to replace the current method for managing tasks and we describe a brief proof of concept showing how Globus Compute could help to schedule jobs and be a tool to connect compute at different facilities.
Listen to the keynote address and hear about the latest developments from Rachana Ananthakrishnan and Ian Foster who review the updates to the Globus Platform and Service, and the relevance of Globus to the scientific community as an automation platform to accelerate scientific discovery.
Unleash Unlimited Potential with One-Time Purchase
BoxLang is more than just a language; it's a community. By choosing a Visionary License, you're not just investing in your success, you're actively contributing to the ongoing development and support of BoxLang.
Experience our free, in-depth three-part Tendenci Platform Corporate Membership Management workshop series! In Session 1 on May 14th, 2024, we began with an Introduction and Setup, mastering the configuration of your Corporate Membership Module settings to establish membership types, applications, and more. Then, on May 16th, 2024, in Session 2, we focused on binding individual members to a Corporate Membership and Corporate Reps, teaching you how to add individual members and assign Corporate Representatives to manage dues, renewals, and associated members. Finally, on May 28th, 2024, in Session 3, we covered questions and concerns, addressing any queries or issues you may have.
For more Tendenci AMS events, check out www.tendenci.com/events
In 2015, I used to write extensions for Joomla, WordPress, phpBB3, etc and I ...Juraj Vysvader
In 2015, I used to write extensions for Joomla, WordPress, phpBB3, etc and I didn't get rich from it but it did have 63K downloads (powered possible tens of thousands of websites).
We describe the deployment and use of Globus Compute for remote computation. This content is aimed at researchers who wish to compute on remote resources using a unified programming interface, as well as system administrators who will deploy and operate Globus Compute services on their research computing infrastructure.
Large Language Models and the End of ProgrammingMatt Welsh
Talk by Matt Welsh at Craft Conference 2024 on the impact that Large Language Models will have on the future of software development. In this talk, I discuss the ways in which LLMs will impact the software industry, from replacing human software developers with AI, to replacing conventional software with models that perform reasoning, computation, and problem-solving.
Climate Science Flows: Enabling Petabyte-Scale Climate Analysis with the Eart...Globus
The Earth System Grid Federation (ESGF) is a global network of data servers that archives and distributes the planet’s largest collection of Earth system model output for thousands of climate and environmental scientists worldwide. Many of these petabyte-scale data archives are located in proximity to large high-performance computing (HPC) or cloud computing resources, but the primary workflow for data users consists of transferring data, and applying computations on a different system. As a part of the ESGF 2.0 US project (funded by the United States Department of Energy Office of Science), we developed pre-defined data workflows, which can be run on-demand, capable of applying many data reduction and data analysis to the large ESGF data archives, transferring only the resultant analysis (ex. visualizations, smaller data files). In this talk, we will showcase a few of these workflows, highlighting how Globus Flows can be used for petabyte-scale climate analysis.
Globus Connect Server Deep Dive - GlobusWorld 2024Globus
We explore the Globus Connect Server (GCS) architecture and experiment with advanced configuration options and use cases. This content is targeted at system administrators who are familiar with GCS and currently operate—or are planning to operate—broader deployments at their institution.
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Healthcare providers often struggle with the complexities of chronic conditions and remote patient monitoring, as each patient requires personalized care and ongoing monitoring. Off-the-shelf solutions may not meet these diverse needs, leading to inefficiencies and gaps in care. It’s here, custom healthcare software offers a tailored solution, ensuring improved care and effectiveness.
Developing Distributed High-performance Computing Capabilities of an Open Sci...Globus
COVID-19 had an unprecedented impact on scientific collaboration. The pandemic and its broad response from the scientific community has forged new relationships among public health practitioners, mathematical modelers, and scientific computing specialists, while revealing critical gaps in exploiting advanced computing systems to support urgent decision making. Informed by our team’s work in applying high-performance computing in support of public health decision makers during the COVID-19 pandemic, we present how Globus technologies are enabling the development of an open science platform for robust epidemic analysis, with the goal of collaborative, secure, distributed, on-demand, and fast time-to-solution analyses to support public health.
AI Pilot Review: The World’s First Virtual Assistant Marketing SuiteGoogle
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(4) AI Ebook Suite Review: https://sumonreview.com/ai-ebook-suite-review
A Comprehensive Look at Generative AI in Retail App Testing.pdfkalichargn70th171
Traditional software testing methods are being challenged in retail, where customer expectations and technological advancements continually shape the landscape. Enter generative AI—a transformative subset of artificial intelligence technologies poised to revolutionize software testing.
4. /29
Kotlin
Introduction
● Statically typed
● Compiles to JVM byte codes or JavaScript
● JVM version is Java compatible both ways
● Intended for industrial use
o Designed for READABILITY
o Relies simple (but powerful) abstractions
o Performance is a priority
o Tooling matters
● Open Source (Apache 2)
o http://github.com/JetBrains/Kotlin
6. /29
Kotlin
Java
type
Kotlin type
byte kotlin.Byte
short kotlin.Short
int kotlin.Int
double kotlin.Double
boolean kotlin.Boolean
Mapped types
Kotlin treats some Java types specially. Such types are
not loaded from Java “as is”, but are mapped to
corresponding Kotlin types. The mapping only matters
at compile time, the runtime representation remains
unchanged. Java’s primitive types are mapped to
corresponding Kotlin types (keeping platform types in
mind):
java.lang.Object kotlin.Any!
int[] kotlin.IntArray!
7. /29
Kotlin
Basic syntax
● You do not need ; to break statements.
● Comments are similar to Java or C#, /* This is comment */ for multi line comments and // for single line
comment.
● Unlike Java, you do not need to match your file name to your class name.
● Like JavaScript, you can create functions outside classes. So there is no need to stuff your functions as static
members of classes like what you do in C# or Java.
● Kotlin has string templates, which is awesome. e.g. "$firstName $lastName" for simple variable name or
"${person.name} is ${1 * 2}" for any expressions. You can still do the string concatenation if you like e.g.
"hello " + "world", but that means being stupid.
● It has no tuple although Kotlin's data classes is an option to use in place of tuple.
● Use function literals to filter and map collections: basic functional programming inside
8. /29
Kotlin
Variable semantic
● There are two keywords for variable declaration, var and val.
● Use var when the variable value is to be modified and val where the variable value will not change after first
assigned.
● This val is similar to readonly keyword in C# or final keyword in Java.
● val variable must be initialized at declaration.
● Unlike Java or C#, you declare the type of a variable after the name, e.g. var firstName : String
● Number primitive types are as follows: Double, Float, Long, Int, Short, Byte. There is no automatic conversion
between types. You have to explicitly convert them.
● More primitive types: Char, String, Boolean.
● All variable declarations in Kotlin must be initialized.
9. /29
Kotlin
Identifiers
4 types of identifiers supported by Scala:
● ALPHANUMERIC IDENTIFIERS
● OPERATOR IDENTIFIERS
● LITERAL IDENTIFIERS
10. /29
Kotlin
ALPHANUMERIC IDENTIFIERS
● An ALPHANUMERIC IDENTIFIERS starts with a letter or underscore,
which can be followed by further letters, digits, or underscores.
● '$' character is a reserved keyword
Legal alphanumeric identifiers:
age, salary, _value, __1_value
Illegal identifiers:
$salary, 123abc, -salary
12. /29
Kotlin
Semantic
- arrays the index used in an array selection expression must be of
integer type
- expressions the two operands to logical && must both be bool type, the result
is bool type
- functions the type of each actual argument in a function call must be
compatible with the formal parameter
- classes if specified, the parent of a class must be a properly declared class
type
- interfaces all methods of the interface must be implemented if a class states
that it implements the interface
13. /29
Kotlin
Semantic (easy stuff)
Class names can be used before being defined
• We can’t check class names
– using a symbol table
– or even in one pass
• Solution
– Pass 1: Gather all class names
– Pass 2: Do the checking
15. /29
Kotlin
Example AST rules
● Before processing e, add definition of x to current
definitions, overriding any other definition of x
● – Recurse
● – After processing e, remove definition of x and restore
old definition of x
for (x : Char in “abc”){ ( x )
Expressions…. ( e )
}
16. /29
Kotlin
Symbol table operations
● addSymbol(x) push x and associated info, such as
x’s type, on the stack
● findSymbol(x) search stack, starting from top, for
x. Return first x found or NULL if none found
● removeSymbol() pop the stack
● enterScope() start a new nested scope
● findSymbol(x) finds current x (or null)
● addSymbol(x) add a symbol x to the table
● checkScope(x) true if x defined in current scope
● exitScope() exit current scope
17. /29
Kotlin
Recall to symbol tables for resolving
fun main(args: Array<String>) {
if (args.size == 0) {
println("Provide a name")
return
}
println("Hello, ${args[0]}!")
//String Interpolation to cut down ceremony.
}
18. /29
Kotlin
Method declaration
● Method names have complex rules
● A method need not to be defined in the class in which it
is used, but in some parent class
● Methods may also be redefined (overridden) (Hard point)
19. /29
Kotlin
Type checking
Type checking computes via reasoning:
If E1 and E2 have certain types, then E3 has a certain type
(e1 : Int AND e2: Int) IMPLIES e1 + e2: Int
We work with hypotheses and conclusions.
So we create type rules.
Ex: is add minus
20. /29
Kotlin
Type checking
Type checking proves facts e: T
– Proof is on the structure of the AST
– Proof has the shape of the AST
– One type rule is used for each AST node
• In the type rule used for a node e:
– Hypotheses are the proofs of types of e’s subexpressions
– Conclusion is the type of e
• Types are computed in a bottom-up pass over the AST
21. /29
Kotlin
Type environment before type check
The type environment gives types to the free
identifiers in the current scope
• The type environment is passed down the AST from
the root towards the leaves
• Types are computed up the AST from the leaves
towards the root
22. /29
Kotlin
Subtyping
Consider:
if e0 then e1 else e2
• The result can be either e1 or e2
• The type is either e1’s type or of e2’s type
• The best we can do is the smallest supertype larger than the type of e1 or e2
23. /29
Kotlin
Subtyping
lub(X,Y), the Least Upper Bound of X and Y, is Z if
– X ⩽ Z AND Y ⩽ Z
Z is an upper bound
– X ⩽ Z’ AND Y ⩽ Z’ IMPLIES Z ⩽ Z’
Z is least among upper bounds
so the least upper bound of two types is their
least common ancestor in the inheritance tree
25. /29
Kotlin
Typing methods
prelude: A method foo and an object foo can coexist in the
same scope
• In the type rules, this is reflected by a separate mapping
M for method signatures
M(C,f) = (T1,. . .Tn,Tn+1)
means in class C there is a method f
f(x1:T1,. . .,xn:Tn): Tn+1 the last one is type of return st
26. /29
Kotlin
Polymorphism (Self type)
class Count {
val i = 0;
fun inc() : Count {
i++
return this
}
};
inc() should return “dynamic type”
class Stock extends Count(var name:String)
{
};
fun main(args: Array<>String){
val a = Stock(“test”)
a = (new Stock).inc (); // fail
… a.name …
};
27. /29
Kotlin
Polymorphism (Self type)
– So, we must redefine inc for each of the subclasses, with a specialized return
type
● Introduce the keyword SELF_TYPE to use for the return value of such
functions
SELF_TYPE is not a dynamic type
– It is a static type
– It helps the type checker to keep better track of types
– It enables the type checker to accept more correct
programs
28. /29
Kotlin
Semantic
Else one Hard aspect:
1) Lamda expressions as new feature of the language:
val positiveNumbers = list.filter {it > 0}
Правила редукции типовых и без типовых лямбда исчислений
Область видимо-сти. Операционная семантика, виды редукций.
Представление термов без использования имён (индексы де Брауна)
Безопасность, продвижение, сохранение.
Простое типизированное лямбда-исчисление: Типы функций.
Отношение типизации. Свойства типизации. Соответствие Карри–Говарда(введения
устранения, при совпадении вычисление).
Стирание типов и типизируемость
Big amount of java programmer. Because it’s well suitable and maintained so JAva platform is very nice ecosystem.
Java platform and Java language there is huge gap.
So for the java programers 10 лет, за монитором наблюдали за языком.
Монитор развивался а язык нет.
Kotlin —
современный статически типизированный объектно-ориентированный язык программирования, компилируемый в байт-код Java и в JavaScript.
Kotlin полностью совместим с Java и предоставляет дополнительные возможности, упрощающие повседневную работу программиста и повышающие продуктивность. Kotlin сочетает в себе лаконичность, выразительность, производительность и простоту в изучении.
Designing a Type Checker
When designing a type checker for a compiler, here’s the process:
1. identify the types that are available in the language
2. identify the language constructs that have types associated with them
3. identify the semantic rules for the language
String fake class String.last(): Char this[]
Checks of many kinds . . . coolc checks:
1. All identifiers are declared
2. Types
3. Inheritance relationships
4. Classes defined only once
5. Methods in a class defined only once
6. Reserved identifiers are not misused
And others . . .
• The requirements depend on the language
val people = hashMapOf<String, Int>()for ((person, age) in people) { println("${person} in ${age} years old")}
Скормить байткоду java создание массива и присваиванию ему метода, к примеру, set то все пройдет нормально.
Но после запуска там не будет никакой ошибки он просто там сдохнет незаметно и все