langur

Langur is an open-source programming language that natively uses decimal floating point, and deals with extremely large and small numbers. Its principles of design are accuracy in calculation and a concise, expressive syntax.

• download langur
• Windows installation instructions
• Linux installation instructions
• source code examples

The following is a partial list of features.

• decimal floating point for numbers (arbitrary precision)
• first-order functions, including closures
• dynamic type system
• automatic memory management
• highly expressive switch expressions
• semi-integrated regex
• ISO 8601 date/time literals
• duration literals
• integer basex notation for any number with base from 2 to 36, such as 2x1010_0010 or -11x123A
• automated for loop over a list, hash, or string, or using a range
• chained string interpolation modifiers
• catching exceptions without explicit try blocks
• both truncating and floor division operators; also remainder and modulus, exponent and root
• optional database operators (null propagating)

Influences include at least the following languages.

Perl, Go, Python, C#, C and Monkey

books

I initially developed langur following very useful books by Thorsten Ball (Writing an Interpreter in Go, Writing a Compiler in Go), but it has changed dramatically since.

I wrote a small book that does not compare to Mr. Ball's books mentioned above. It explains the design of some of langur's advanced features, in its stack-based virtual machine. See a free preview chapter at opcodebook.com.