"Ruby" (External Evaluation System)
Details

- Ruby Version 2.0 and higher is supported.
- To configure Ruby for use in the Wolfram Language, follow the instructions from the Configure Ruby for ExternalEvaluate workflow.
ExternalEvaluate Usage

- ExternalEvaluate["Ruby",code] executes the code string in a Ruby REPL and returns the results as a Wolfram Language expression.
- ExternalEvaluate["Ruby""String",code] executes the code string in a Ruby REPL and returns the output as a Wolfram Language string.
Data Types

- The following Ruby built-in types are supported:
-
Array List array of values BigDecimal Real arbitrary-precision real number Bignum Integer arbitrary-sized integer boolean TrueFalse Boolean values Complex Complex complex number Fixnum Integer machine-size number Float Real real-valued number Hash Association associative array nil Null null value Rational Rational rational number String String sequence of character values
Examples
open allclose allBasic Examples (3)
Evaluate 2+2 in Ruby and return the result:
Type > and select Ruby from the drop-down menu to get a code cell that uses ExternalEvaluate to evaluate:
Scope (20)
Concatenate strings in Ruby and return the result:
Hashes in Ruby are returned as associations:
Session Options (9)
"ReturnType" (3)
For the Ruby evaluation system, the default return type is "Expression":
Numbers, strings, lists and associations are automatically imported for the "Expression" return type:
The return type of "String" returns a string of the result by calling the Ruby method to_s:
"Version" (1)
Command Options (10)
"Command" (3)
When only a string of Ruby code is provided, the command is directly executed:
The above is equivalent to writing the command using this form:
Use a File wrapper to run the code in a file:
The above is equivalent to writing the command using this form:
Put code in a CloudObject:
Evaluate directly from the cloud:
The above is equivalent to writing the command using this form:
"ReturnType" (1)
"Arguments" (2)
Use "Arguments" to call a Ruby function with arguments:
When a non-list argument is provided, a single argument is passed to the function:
If you need to pass a list as the first argument, you must wrap it with an extra list explicitly:
You can define a function inside "Command" and directly call it with "Arguments":
The same result can be achieved by using a Rule:
You can also pass arguments by creating an ExternalFunction:
"TemplateArguments" (3)
When running a command, you can inline a TemplateExpression:
You can explicitly fill TemplateSlot using "TemplateArguments":
When a non-list argument is provided, a single template argument is passed to the template:
If you need to pass a list as the first argument, you must wrap it with an extra list explicitly:
You can name template slots and use an Association to pass named arguments to the template: