fluidattacks-blends-domain 0.26.0

Blends functional core: pure AST graph to syntax graph (no_std)
Documentation
use crate::{
    query::adj_ast,
    syntax::{builders::assignment::build_assignment_node, SyntaxGraphArgs, SyntaxGraphError},
    utilities::text_nodes::node_to_str,
    NodeId,
};

pub fn reader(
    args: &mut SyntaxGraphArgs<'_>,
    n_id: NodeId,
) -> Result<Option<NodeId>, SyntaxGraphError> {
    let graph = args.ast_graph;
    let children = adj_ast(graph, n_id, Some(1), &[]);

    let (operator, value_id, variable_id) = if children.len() >= 3 {
        let op = children
            .get(1)
            .copied()
            .ok_or(SyntaxGraphError::UnexpectedAstShape)?;
        let op_text = node_to_str(graph, op);
        let value = children
            .get(2)
            .copied()
            .ok_or(SyntaxGraphError::MissingAstNode)?;
        let variable = children
            .first()
            .copied()
            .ok_or(SyntaxGraphError::MissingAstNode)?;
        (Some(op_text), value, variable)
    } else {
        let variable = children
            .first()
            .copied()
            .ok_or(SyntaxGraphError::MissingAstNode)?;
        let value = children
            .last()
            .copied()
            .ok_or(SyntaxGraphError::MissingAstNode)?;
        (None, value, variable)
    };

    build_assignment_node(args, n_id, variable_id, Some(value_id), operator).map(Some)
}