# Safe-Call Operator Published articles for Safe-Call Operator. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## KotlinConf 2025 Announcements DevFeed: [KotlinConf 2025 Announcements]() Original publisher: [Read original article]() Published: 2025-06-03T00:00:00Z Content type: article Language: en Sources: [Kt. Academy]() Topics: [Kotlin](), [destructuring](), [Exception](), [union types](), [syntax](), [Safe-Call Operator]() Tags: [announcements](), [destructuring](), [exceptions](), [kotlin](), [kotlinconf](), [new-features](), [safe-call-operator](), [syntax](), [union-types](), [workshop-learning-programming]() ### AI overview The article summarizes announcements from KotlinConf 2025, including K2 becoming stable, upcoming name-based destructuring, and rich errors with language-level support for result-or-error types and related operators. ### Source excerpt The greatest announcements from KotlinConf 2025. ## Nulls and Null Safety DevFeed: [Nulls and Null Safety]() Original publisher: [Read original article]() Author: author@typealias.com (Dave Leeds) Published: 2021-03-30T00:00:00Z Content type: article Language: en Sources: [Dave Leeds on Kotlin - typealias.com]() Topics: [Null-Safety]() Tags: [class](), [elvis-operator](), [introduction](), [kotlin](), [learn-to-program](), [not-null-assertion-operator](), [null](), [null-safety](), [nulls](), [optional](), [program](), [programming](), [safe-call-operator](), [smart-cast](), [value](), [variable]() ### AI overview The excerpt introduces nulls as a way for a variable to hold no value, unlike the previously shown String, Int, and Boolean variables that were assigned values. It begins an example in which James collects coffee ratings and wants to track them in a Kotlin program; the excerpt ends before showing the class or explaining null safety. ### Source excerpt So far in this book, every time that we created a variable, whether it was a String, an Int, or a Boolean, we assigned a value to it. There are times, though, when we need to create a variable that might not actually hold a value! This brings us to the exciting topic of nulls! Introduction to Nulls James has set up a coffee stand downtown, and he's ready to start sharing his fine brew! ## Top 10 Kotlin Stack Overflow questions, pt 3 - nulls and such DevFeed: [Top 10 Kotlin Stack Overflow questions, pt 3 - nulls and such]() Original publisher: [Read original article]() Author: Márton Braun Published: 2018-05-08T08:00:00Z Content type: tutorial Language: en Sources: [zsmb.co]() Topics: [Kotlin](), [Stack Overflow](), [Code]() Tags: [android](), [kotlin](), [marton-braun](), [null](), [safe-call-operator](), [smart-cast](), [stack-overflow](), [zsmb](), [zsmb-co](), [zsmb13](), [zsmbco]() ### AI overview The third and final article in a series explains Kotlin nullability, including why smart casts do not work on mutable properties and how the null assertion operator can cause runtime crashes. ### Source excerpt The third and final part covers topics of nullability and some small extras to wrap up the series. ## Choosing between with() and run() DevFeed: [Choosing between with() and run()]() Original publisher: [Read original article]() Author: author@typealias.com (Dave Leeds) Published: 2017-09-14T01:23:30Z Content type: comparison Language: en Sources: [Dave Leeds on Kotlin - typealias.com]() Topics: [scope function]() Tags: [bytecode](), [decompiler](), [extension-function](), [intellij](), [kotlin](), [library](), [nulls](), [programming](), [readability](), [receiver](), [run](), [safe-call-operator](), [scope-functions](), [with]() ### AI overview Kotlin's `with()` and receiver `run()` both expose the object as `this` inside the block and return the block's result; the excerpt says they compile almost identically. The key practical difference shown is that extension `run()` can be called with a safe-call (`?.`), so a null receiver skips the block and yields null. Passing a nullable value to `with()` still executes its block, so it does not provide the same null interception. The excerpt begins a readability discussion but cuts off before stating its conclusion. ### Source excerpt In Kotlin's standard library, the Standard.kt file contains a number of scope functions that put a receiver object into a new scope as either this or as an argument (e.g., it). The with() function tends to be a bit of an outlier. The others are all extension functions, so they're invoked on an object. with(), on the other hand, takes its receiver (the object that it's operating upon) as an argument. ## Java Optionals and Kotlin Nulls DevFeed: [Java Optionals and Kotlin Nulls]() Original publisher: [Read original article]() Author: author@typealias.com (Dave Leeds) Published: 2017-09-01T00:00:00Z Content type: tutorial Language: en Sources: [Dave Leeds on Kotlin - typealias.com]() Topics: [Java](), [Kotlin]() Tags: [exception](), [extension-function](), [filter](), [java](), [java-8](), [kotlin](), [migration-guide](), [null](), [null-safety](), [optional](), [programming](), [safe-call-operator](), [standard-library](), [transformation]() ### AI overview A guide to translating Java Optional usage into idiomatic Kotlin null-safety patterns. It compares creation, transformation, filtering, and conditional operations, while noting trade-offs and cases where Kotlin nullable types replace Optional. ### Source excerpt When Java 8 introduced Streams for operating on collections of data, it also introduced a similar concept, Optional, which has many methods that are similar to Stream, but operates on a single value that might or might not be present. As you migrate your projects from Java to Kotlin, you might come across some Optional objects. What should you do? Should you leave them as Optional, or change them to more idiomatic Kotlin?