6.51 Eval

8.12

6.51 Eval🔗ℹ

An evaluator is an interactive evaluation context. Each evaluator has its own set of bindings and, potentially, its own set of module declarations. A Rhombus read-eval-print loop (REPL) is backed by an evaluator, for example.

function

fun eval(seq :: Syntax,

~as_interaction: as_interaction :: Any = #false)

Evaluates a term, group, or multi-group sequence seq in the current evaluator.

If as_interaction is true, then seq is evaluated as if in a read-eval-print loop. Depending on the bindings of the current evaluator (as determined by Evaluator.current), that can be different that evaluating non-interaction top-level forms.

A suitable evalutor must have been created and installed as the value of the Evaluator.current context parameter, since the default evaluator is empty.

> parameterize { Evaluator.current: Evaluator.make_rhombus() }:
eval('1 + 2')
3

annotation

Evaluator

Represents an evaluator for interactive evaluation via eval. An evaluator is installed as the current one using Evaluator.current, usually via parameterize.

function

fun Evaluator.make_rhombus() :: Evaluator

Creates a fresh evaluator with rhombus imported.

function

fun Evaluator.make_rhombus_empty() :: Evaluator

Creates a fresh evaluator with the rhombus module attached, but not imported.

function

fun Evaluator.import(mod :: ModulePath) :: Void

Imports mod into the current evaluator, even if the import definition form is not available in the evaluator itself.

context parameter

Parameter.def Evaluator.current :: Evaluator

A context parameter for the current evaluator.

1	Rhombus Essentials
2	Collections and Iteration
3	Syntax Objects and Macros
4	Classes and Interfaces
5	Static Information and Binding
6	Core Reference
7	Meta and Macros Reference
8	Rhombus Static by Default
9	Libraries
10	Naming Conventions

6.1	General Forms
6.2	Definitions
6.3	Namespaces
6.4	Import
6.5	Export
6.6	Functions
6.7	Operators
6.8	Classes and Interfaces
6.9	Veneers
6.10	Mutable Variables and Assignment
6.11	Repetitions
6.12	Block
6.13	Conditionals
6.14	Matching
6.15	Iteration
6.16	Recursion
6.17	Context Parameters
6.18	Exceptions
6.19	Continuations
6.20	Implicit Forms
6.21	Static and Dynamic Lookup
6.22	Modules and Submodules
6.23	Booleans
6.24	Numbers
6.25	Characters
6.26	Strings
6.27	Keywords
6.28	Symbols
6.29	Byte Strings
6.30	Lists
6.31	Pairs and Pair Lists
6.32	Mutable Lists
6.33	Arrays
6.34	Maps
6.35	Sets
6.36	Boxes
6.37	Indexables
6.38	Listables
6.39	Sequences
6.40	Appendables
6.41	Comparables
6.42	Paths
6.43	Source Locations
6.44	Void
6.45	Equality
6.46	Dot
6.47	Multiple Values
6.48	Annotations
6.49	Enumerations
6.50	Input and Output
6.51	Eval
6.52	Syntax Objects
6.53	Syntax Classes
6.54	Simple Expression Macros
6.55	Unit Testing