Hello, World

Welcome to Flow blockchain, Let's call a contract on Testnet.

Calling a contract

There exists a HelloWorld Contract on Testnet. Scripts are used to call contracts. For the purposes of this quick start, we are embedding Flow Runner website to run a script against Testnet. For reference Flow Runner website

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import HelloWorld from 0x9dca641e9a4b691b

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pub fun main(): String {

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return HelloWorld.greeting

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}

Copy the script above into Flow Runner and click "Execute Script" Then scroll down to see the output.

Contract on Testnet

Here is the contract, see the simple Cadence syntax to create a contract.

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pub contract HelloWorld {

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pub var greeting: String

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pub fun changeGreeting(newGreeting: String) {

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self.greeting = newGreeting

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}

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init() {

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self.greeting = "Hello, World!"

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}

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}

You can see how simple it is to call a method on a contract. There are no costs associated with calling contracts. Continue to learn how to create your own custom contracts and deploying with Flow CLI

Check out the Flow CLI