When comparing Apache Groovy vs Swift, the Slant community recommends Swift for most people. In the question“What is the best programming language to learn first?” Swift is ranked 36th while Apache Groovy is ranked 63rd.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Integrates well with Java
This link adds some interesting points explaining how Groovy integrates better with Java than e.g. Scala. If you want to write classes that can be consumed by Java classes, or easily consume existing Java code, Groovy is probably a pretty wise choice. It can be statically compiled and supports optional typing, which makes it much more maintainable for larger projects than e.g. JRuby.
Pro Dynamic and static type checking and compiling
Pro Relatively large ecosystem
Groovy is a popular JVM language with a rather large and developed ecosystem. It has several web frameworks (the most famous being Grails) and many libraries.
Pro Closure support
Pro Nice syntax
Pro Modern syntax
Pro Swift is closer to other platforms
Apple’s modern programming language is easier to understand for non-iOS developers and minimizes time for additional explanations and clarifications. Moreover, Swift can be used as a script language. It is an interesting solution for the iOS community to unify writing of build scripts. At the time being iOS developers are split up in regard to this activity. Some of them write build scripts in Bash, others use Ruby, Python, etc. Swift gives an amazing opportunity to be applied to all iOS programming needs.
More details can be found here https://mlsdev.com/blog/51-7-advantages-of-using-swift-over-objective-c
Pro Works with Apple's Cocoa and Cocoa Touch frameworks
Pro Can be used as a Just-In-Time language
Pro Inherent parallelism
Pro Low memory footprint due to reference counting
Pro Backed by Apple
Pro Performance speed comparable to native C
Pro Swift has some clever tricks up its sleeve
Due to having elements of a functional programming language. Things like 'map' and 'filter' for example.
Pro Uses LLVM compiler and Obj-C runtime allowing C, Objective-C, Objective-C++ and Swift code to run side by side within a single program
Cons
Con Compile Static and generics have some problems
Con Swift is a moving target
They've released 1.2 so far, and 2.0 is coming soon. Every small update brings adjustments to paradigms (such as how to do type casting) that can be a little frustrating to absorb. Objective C was also constantly updating, however, but not at the same rate these days.