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Statements | Statements control execution in the Flux functional data scripting language. |
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{{% note %}} This document is a living document and may not represent the current implementation of Flux. Any section that is not currently implemented is commented with a [IMPL#XXX] where XXX is an issue number tracking discussion and progress towards implementation. {{% /note %}}
A statement controls execution.
Statement = OptionAssignment
| BuiltinStatement
| VariableAssignment
| ReturnStatement
| ExpressionStatement .
Import declaration
ImportDeclaration = "import" [identifier] string_lit .
A package name and an import path is associated with every package.
The import statement takes a package's import path and brings all of the identifiers
defined in that package into the current scope under a namespace.
The import statement defines the namespace through which to access the imported identifiers.
By default the identifier of this namespace is the package name unless otherwise specified.
For example, given a variable x
declared in package foo
, importing foo
and referencing x
would look like this:
import "import/path/to/package/foo"
foo.x
Or this:
import bar "import/path/to/package/foo"
bar.x
A package's import path is always absolute. A package may reassign a new value to an option identifier declared in one of its imported packages. A package cannot access nor modify the identifiers belonging to the imported packages of its imported packages. Every statement contained in an imported package is evaluated.
Return statements
A terminating statement prevents execution of all statements that appear after it in the same block. A return statement is a terminating statement.
ReturnStatement = "return" Expression .
Expression statements
An expression statement is an expression where the computed value is discarded.
ExpressionStatement = Expression .
Examples of expression statements
1 + 1
f()
a
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