nd

Language experiment involving concatenation, stacks and arrays, inspired by APL and Forth. The name nd is a shorthand for n-dimensional, and follows the tradition of un-Googleable array language names.

Built-in Words

IO

• _ Print the top stack value.

Control flow

• if Conditionally evaluate the next code based on the truthiness of the top stack element. If falsy, continue from next then.
• then Marker to identify branch end.
• do Repeat the following word n times, where n is the value of the top stack element.

Boolean operators

• and Logical and between top two stack elements. If each element has multiple values, perform element-wise and.
• or Logical or between top two stack elements. If each element has multiple values, perform element-wise _or.

All boolean operators repeat the top stack element, so [ 1 0 1 ] 1 v evaluates to [ 1 1 1 ].

Equality

• eql Test value-wise equality between top two stack elements.

Arithmetic operators

• + Value-wise addition between top two stack elements.
• - Value-wise subtraction between top two stack elements.
• * Value-wise multiplication between top two stack elements.
• / Value-wise division between top two stack elements.

All arithmetic operators repeat the top stack element, so [ 1 2 3 ] 1 + evaluates to [ 2 3 4 ].

In-element manipulation

• cat Concatenate top stack element to the following stack element.
• trm Transmute the top stack element into individual elements.
• len Push the length of the top stack element onto the stack.

Stack manipulation

• dup Duplicate top stack element.
• pop Pop top stack element.
• swp Swap the top two stack elements.
• rot Move the bottom stack element to the top.
• clr Clear the stack.
• clr1 Clear all but the top stack element.

Definitions

• : Start word definition.
• ; End word definition.
• [ Start element definition. If element only contains a single value, the brackets can be omitted.
• ] End element definition.