Jaakko Pallari jpallari

Error handling pitfalls in Scala

There are multiple strategies for error handling in Scala.

Errors can be represented as [exceptions][], which is a common way of dealing with errors in languages such as Java. However, exceptions are invisible to the type system, which can make them challenging to deal with. It's easy to leave out the necessary error handling, which can result in unfortunate runtime errors.

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	I hereby claim:

	* I am jpallari on github.
	* I am jkpl (https://keybase.io/jkpl) on keybase.
	* I have a public key ASDo6ByeSB8oz6MvyueMdC6F17j0uuna3o7qoHRXhNKr4Qo

	To claim this, I am signing this object:

	#!/usr/bin/env node
	/*
	Convert a CDK app manifest file to a stack dependency tree in Mermaid format.
	*/
	const fs = require('fs');

	function dependencyTreeInMermaid(data) {
	const names = {};
	const links = [];

	<?xml version="1.0" encoding="UTF-8"?>
	<!DOCTYPE keyboard PUBLIC "" "file://localhost/System/Library/DTDs/KeyboardLayout.dtd">
	<!--Last edited by Ukelele version 2.0.1 on 2010-08-26 at 17:40 (GMT+02:00)-->
	<keyboard group="0" id="2" name="U.S. International w/o dead keys" maxout="1">
	<layouts>
	<layout first="0" last="17" modifiers="f4" mapSet="16c"/>
	<layout first="18" last="18" modifiers="f4" mapSet="994"/>
	<layout first="21" last="23" modifiers="f4" mapSet="994"/>
	<layout first="30" last="30" modifiers="f4" mapSet="994"/>
	<layout first="194" last="194" modifiers="f4" mapSet="994"/>

	param (
	[Parameter(Mandatory=$false)]
	[switch]$Disable
	)

	$script:regKeyPath = "HKLM\SYSTEM\CurrentControlSet\Control\DeviceGuard\Scenarios\HypervisorEnforcedCodeIntegrity"

	If ($Disable) {
	Write-Host "Disabling HyperV"
	bcdedit /set hypervisorlaunchtype off

	---
	apiVersion: v1
	kind: Service
	metadata:
	name: demo-ksql-server
	labels:
	app: demo-ksql-server
	spec:
	ports:
	- port: 8088

	FROM debian:stable-slim

	RUN apt-get update && \
	apt-get install -y ca-certificates curl && \
	rm -rf /var/lib/apt/lists/*

	ENV SAML2AWS_VERSION=2.16.0
	ENV SAML2AWS_DOWNLOAD_URL=https://github.com/Versent/saml2aws/releases/download/v${SAML2AWS_VERSION}/saml2aws_${SAML2AWS_VERSION}_linux_amd64.tar.gz

	RUN curl -L "$SAML2AWS_DOWNLOAD_URL" -o saml2aws.tar.gz && \

	#!/bin/sh
	#
	# This script deploys the given manifest,
	# tracks the deployment, and rolls back on failure.
	#
	# First execute this with "myapp.yaml" and then try it with "myapp.failing.yaml"
	#

	MANIFEST_PATH=$1
	DEPLOYMENT_NAME=myapp

	package dwgraphitedemo

	import java.lang.management.ManagementFactory
	import java.util.concurrent.TimeUnit

	import com.codahale.metrics.graphite.{Graphite, GraphiteReporter}
	import com.codahale.metrics.SharedMetricRegistries
	import com.codahale.metrics.jvm._
	import com.twitter.finagle.http.{Request, Response, Status}
	import com.twitter.finagle.{Http, Service}

	<?xml version="1.0" encoding="UTF-8"?>
	<!DOCTYPE keyboard PUBLIC "" "file://localhost/System/Library/DTDs/KeyboardLayout.dtd">
	<!--Last edited by Ukelele version 2.2.4 on 2013-02-08 at 22:01 (UTC+2.00)-->
	<keyboard group="0" id="5591" name="AltFin" maxout="1">
	<layouts>
	<layout first="0" last="17" modifiers="f4" mapSet="16c"/>
	<layout first="18" last="18" modifiers="f4" mapSet="984"/>
	<layout first="21" last="23" modifiers="f4" mapSet="984"/>
	<layout first="30" last="30" modifiers="f4" mapSet="984"/>
	<layout first="194" last="194" modifiers="f4" mapSet="984"/>