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[New post] JavaScript Constants

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JavaScript Constants

by satya

CONSTANTS

The const keyword was introduced in ES6 (2015).

Variables defined with const cannot be Redeclared.
Variables defined with const cannot be Reassigned.
Variables defined with const have Block Scope.
JavaScript const variables must be assigned a value when they are declared.
Declaring a variable with const is similar to let when it comes to Block Scope.

When to use JavaScript const?

As a general rule, always declare a variable with const unless you know that the value will change.

Use const when you declare:

A new Array
A new Object
A new Function
A new RegExp

Constant Objects and Arrays

It does not define a constant value. It defines a constant reference to a value.

Because of this you can NOT:

Reassign a constant value
Reassign a constant array
Reassign a constant object

Change the elements of constant array
Change the properties of constant object

Constant Arrays

 // You can create a constant array: const cars = ["Saab", "Volvo", "BMW"];  // You can change an element: cars[0] = "Toyota";  // You can add an element: cars.push("Audi");

Constant Objects

 // You can create a const object: const car = {type:"Fiat", model:"500", color:"white"};  // You can change a property: car.color = "red";  // You can add a property: car.owner = "Johnson";

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satya | October 26, 2021 at 6:00 am | Categories: Javascript | URL: https://wp.me/p15W6i-1Rb

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[New post] Underground Rowing – Part 1: Boat Race Posters 1910 – 1930

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Underground Rowing – Part 1: Boat Race Posters 1910 – 1930

by HTBS

*The medium is the message. A cubist/modernist London Transport (LT) poster from 1933 prompting the use of advertising posters on the capital's underground railway network.*

26 October 2021

By Tim Koch

Tim Koch goes bill posting.

Those who still have to regularly endure commuting on London's underground and bus network may draw little comfort from the fact that the organisation that runs the capital's public transport was for many years Britain's greatest patron of poster art and was a pioneer of graphic design with a world-wide reputation.

The website of the London Transport Museum gives a history of London Transport posters:

The modern graphic poster came into use in the 1890s, revolutionising the fields of publicity, advertising and propaganda…

Frank Pick… was given responsibility for the Underground's publicity in 1908. Despite a background as a solicitor and administrator, Pick instantly recognised the potential of posters…

Pick's theory behind commissioning was that posters could "move from the most literal representation to the wildest impression so long as the subject remained clear." He knew that traditional posters would reassure the public, but he also recognised that public taste could be extended by exposure to the unfamiliar, the adventurous and even the shocking…

During the 1920s and 1930s the Underground Group's posters reached a peak of stylistic quality. In 1927 the art critic of "The Times" claimed, "there can be no doubt at all that the credit for the earliest consistent use of good posters of any kind belongs to the Underground…"

Encouraging travel by bus, tram and underground to sporting events, notably London's big day out, the Oxford - Cambridge Boat Race, was a major and constant part of London Transport's ongoing poster campaign and this effort resulted in some of its finest works. HTBS has mentioned LT's Boat Race posters several times previously but here I have attempted to record every poster it produced urging Londoners to travel to Putney, Hammersmith or Mortlake to view the great annual spectacle.

Boat Race crowds on Hammersmith's Lower Mall in 1937 and 2011. Then and now, the majority would have arrived via London Transport or its 2000 successor, Transport for London. Strictly speaking, LT only came into existence in 1933 but its predecessors were complex, and it is easier to use this most famous of brand names.

In 2012, the London Transport Museum put 300 of its original posters up for auction at Christie's. Presumably these were duplicates as it still has 5000 posters in its archive. The catalogue for the Posters With A Purposesale is still online, together with the prices realised. The rowing ones are in Lots 253 to 270 and, while most went for between £1000 and £5000, a Boat Race poster from 1921 went for £30,000, from 1930 for over £16,000 and from 1923 for over £10,000.

Even in modern times, when free entertainment is not prized as much as in the past, when sophisticated visual coverage is easily accessible, and when the public interest in rowing is far less than before the Second World War, a survey found that, in 2017, 250,000 people watched the Boat Race from the river bank and that 50,000 of these came from outside of London. Only ten per cent arrived by car, forty per cent by foot and half came by public transport.

Assuming that LT's Boat Race poster run started in 1910 and ended in 1959, the only race years that I cannot find a poster for are 1922, 1946 to 1949, 1952 and 1957. I speculate that none were made during the worst of the post-war austerity years, 1946 to 1949, but am surprised about the other three missing years. Does anyone know of posters for 1922, 1952 or 1957?