Error Handling and Exceptions

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• Q134: How do I use try/catch to handle exceptions in EK9?
• Q135: How does try/catch/finally work in EK9?
• Q136: How do I throw exceptions in EK9?
• Q137: How do I manage resources with try-with-resources in EK9?
• Q138: How do I catch specific exception types in EK9?
• Q139: When should I use try/catch vs Result for error handling?
• Q304: What is the require statement and when should I use it?
• Q305: What is the difference between require, assert, and throw?
• Q306: How do I test that code throws an exception in EK9?
• Q307: How do I verify that code does not throw an exception in EK9?
• Q308: How do I handle different exception types in EK9 without casting?
• Q802: Why does EK9 reject manual close of local resources?
• Q803: What happens when a closeable resource is never closed?
• Q1009: In Go I return (value, error) and check if err != nil. What does EK9 use instead?
• Q1014: In Python I use try/except for error handling. How does EK9's try/catch compare?
• Q1431: How does an EK9 program set its exit status?
• Q1432: How do I end my program with a chosen exit code when something fails?
• Q1433: What exit code does an uncaught Exception with no exit code give, and what about one that wraps a cause?
• Q1434: What is a Panic in EK9 and when does the language raise one?
• Q1435: What exit code does a failed require or assert give?
• Q1436: Should I catch an Exception that carries an exit code, or let it end the program?
• Q1437: My ek9 command exited 3 - was that the compiler or my program?
• Q1520: When does EK9 close a closeable value, and where may I keep one?
• Q1600: Who closes a closeable value, and can I close one myself?
• Q1620: Can a method return a closeable it already holds, or must it return a new one?
• Q1640: Can I keep a closeable in a variable of a trait or Any type?
• Q1660: Can I call close() on a resource like a method?
• Q1700: How do I shut a server down from a handler when only its owner may close it?
• Q1720: Why can't a closeable have an open() method that returns this - how do I acquire a resource?
• Q1740: How do I let other code use a resource my object owns without letting it close or keep it?
• Q1780: Can I put a closeable resource in a List, an Optional or my own generic type?
• Q1840: Can I give my object a resource I have already opened?
• Q1841: How do I reconnect or replace a resource my object holds?
• Q1842: In what order are the resources my object holds closed?
• Q1843: Can a type that holds a closeable resource use 'default operator :=:'?
• Q1860: Which of my types must declare their own operator close, and what may that close do?
• Q1880: How do I release the resources my class holds - and what does 'default operator close' close for me?
• Q1900: How can my code use a closeable resource it does not own?
• Q1901: How do I broadcast a message to every open connection, like a chat server, when I cannot keep a list of connections?
• Q1902: What happens when a close throws an exception - are the other resources still closed?
• Q1920: How do I see the close failures that were suppressed onto the exception I caught?
• Q1940: When exactly is a closeable I never name closed - what if it is made inside an 'and', a ternary or a coalescing operator?