Method new

std/src/data.rs:68–99

Creates a new `READ` command.

(index: Rc<RefCell<usize>>)

impl ReadCommand {
    /// Creates a new `READ` command.
    pub fn new(index: Rc<RefCell<usize>>) -> Rc<Self> {
        Rc::from(Self {
            metadata: CallableMetadataBuilder::new("READ")
                .with_syntax(&[(
                    &[],
                    Some(&RepeatedSyntax {
                        name: Cow::Borrowed("vref"),
                        type_syn: RepeatedTypeSyntax::VariableRef,
                        sep: ArgSepSyntax::Exactly(ArgSep::Long),
                        require_one: true,
                        allow_missing: false,
                    }),
                )])
                .with_category(CATEGORY)
                .with_description(
                    "Extracts data values from DATA statements.
DATA statements can appear anywhere in the program and they register data values into an array of \
values.  READ is then used to extract values from this array into the provided variables in the \
order in which they were defined.  In other words: READ maintains an internal index into the data \
array that gets incremented by the number of provided variables every time it is executed.
The variable references in the vref1..vrefN list must match the types or be compatible with the \
values in the corresponding position of the data array.  Empty values in the data array can be \
specified by DATA, and those are converted into the default values for the relevant types: \
booleans are false, numbers are 0, and strings are empty.
Attempting to extract more values than are defined by DATA results in an \"out of data\" error.
The index that READ uses to extract DATA values can be reset by RESTORE and, more generally, by \
CLEAR.",
                )
                .build(),
            index,
        })
    }
}

#[async_trait(?Send)]