Node conf ar 2018.

Transcript

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   ¡Hola!

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   https://github.com/tc39/proposals

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   v. NodeConf Ar

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   @wmsbill What is this?

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   @wmsbill this in the global scope Browser - window Web

   worker - self NodeJS - module.exports
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   @wmsbill this inside a function?

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   @wmsbill this inside a function?

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   @wmsbill What is this?

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   @wmsbill What is this?

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    @wmsbill this inside a function Browser - window NodeJS -

    global object
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    @wmsbill this with new operator

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    @wmsbill this with new operator

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    @wmsbill this with strict mode

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    @wmsbill this with strict mode

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    @wmsbill Setting this value Function.prototype.call Function.prototype.apply Function.prototype.bind new operator Object

    member function
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    @wmsbill Setting this value

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    @wmsbill How to make this predictable? Reasoning the value of

    this is tricky Function.prototype.bind Arrow function () => {}
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    None
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    With .bind()

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    With Arrow

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    @wmsbill Calling a knowing function

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    @wmsbill Extracting a method from an object

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    None
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    @wmsbill Two syntaxes Unary : :context.method() Binary context: :method()

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    @wmsbill Unary syntax

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    @wmsbill Binary syntax

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    @wmsbill

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    @wmsbill

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    @wmsbill

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    @wmsbill Bind operator is good for virtual methods But relies

    on this to be bound
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    @wmsbill Composing without this

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    @wmsbill

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    @wmsbill

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    None
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    @wmsbill Pipeline operator |> It is a syntax sugar for

    function composition It creates a way to streamline a chain of functions
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    @wmsbill Pipeline operator |>

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    @wmsbill

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    @wmsbill

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    @wmsbill

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    @wmsbill Function with more params

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    @wmsbill Function with more params

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    @wmsbill Awaiting a function

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    @wmsbill Awaiting a function

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    @wmsbill Awaiting a function

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    @wmsbill Awaiting a function

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    @wmsbill Awaiting a function

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    None
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    @wmsbill Smart pipeline

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    @wmsbill Smart pipeline Two types bare style and topic style

    () or [] are disallowed in bare style When () or [] is needed, topic style is used # token is subject to change
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    @wmsbill What about curry?

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    None
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    @wmsbill F# pipeline proposal Extends the minimal proposal with an

    await step Await step waits for the resolution of the previous step
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    @wmsbill F# pipeline proposal

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    @wmsbill

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    @wmsbill Partial application f(…) arity = n; partialapp(f(…)) arity =

    m; m < n
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    @wmsbill

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    @wmsbill

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    @wmsbill Partial application in ES Achievable by Function.prototype.bind .bind() binds

    context and parameters
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    @wmsbill

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    @wmsbill What about currying? We can achieve partial application with

    curry Curry ≠ Partial application Curry returns arity n-1
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    @wmsbill

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    @wmsbill Partial application with arrow function

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    None
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    @wmsbill Partial application proposal Creates two new parameters tokens ?

    For single argument . . . for multiple parameters (not in the initial spec anymore)
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    @wmsbill Partial application syntax

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    @wmsbill With arbitrary parameter

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    None
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    @wmsbill Partial application in template string

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    @wmsbill Partial application in template string

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    None
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    @wmsbill The . . . token Spread the unbound parameters

    Useful when you want to bound first or last parameter
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    @wmsbill The . . . token

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    @wmsbill The . . . token

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    @wmsbill Partial application + pipeline

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    @wmsbill Partial application + pipeline

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    @wmsbill Should I use all of it in production? These

    proposal are in very early stage The adoption of one, may change the syntax/semantics of other Not production ready (yet)
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    https://medium.com/@wmsbill https://twitter.com/wmsbill wmsbill@gmail.com https://www.smashingmagazine.com/2018/10/taming-this-javascript-bind- operator/

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    ¡Gracias!