A `comfortable' programming language should have...

* implicit dynamic (and preferably strong) typing
  - makes it easier to change and mix types, which can be a Good Thing
  - faster to read/write/compile

* garbage collection
  - no memory leaks
  - less burden on the programmer

* REPL
  - speeds up the coding process
  - necessary for experimenting

* first-class functions & closures
  - many situations are easier to handle
  - functional style can often be more readable

* powerful metaprogramming (`macros')
  - shorter code, less code duplication
  - domain-specific languages


Also, it is nice to have...

- simple syntax
- comfortable Emacs mode
- lots of libraries
- a nice object system
- optional type hints
- good compiler (preferably to (fast) native code as well as bytecode)


So what languages have these features?

- Lisps (Common Lisp, Scheme, Clojure, etc.)
- Julia
- Dylan
- Factor

Other nice languages with most of the `comfortable' features,
but without (real) metaprogramming:

- Python
- Smalltalk
- ...?