Method expression

source/python.js:22196–22355

(expr, context)

    }

    expression(expr, context) {
        const ast = this.ast;
        const builtins = this.builtins;
        const typing = this.typing;
        const self = context.get('self');
        switch (expr.__class__.__name__) {
            case 'Assign': {
                const [target] = expr.targets;
                if (target instanceof ast.Name) {
                    const value = this.expression(expr.value, context);
                    context.set(target.id, value);
                    return undefined;
                } else if (target instanceof ast.Subscript) {
                    if (target.value instanceof ast.Name &&
                        target.slice instanceof ast.List &&
                        target.slice.elts.length === 1) {
                        const index = this.expression(target.slice.elts[0], context);
                        const id = target.value.id;
                        if (id === '__annotations__') {
                            context.set(id, context.get(id) || {});
                        }
                        const obj = context.get(id);
                        const value = this.expression(expr.value, context);
                        if (obj instanceof Map) {
                            obj.set(index, value);
                        } else {
                            obj[index] = value;
                        }
                        return undefined;
                    }
                } else if (target instanceof ast.Attribute) {
                    const obj = this.expression(target.value, context);
                    const value = this.expression(expr.value, context);
                    obj[target.attr] = value;
                    return undefined;
                } else if (target instanceof ast.Tuple) {
                    context.target.push(target.elts);
                    const value = this.expression(expr.value, context);
                    context.target.pop();
                    if  (target.elts.every((elt) => elt instanceof ast.Name)) {
                        if (target.elts.length < value.length) {
                            throw new python.Error(`ValueError: too many values to unpack (expected ${target.value.length}, actual ${value.length}).`);
                        }
                        if (target.elts.length > value.length) {
                            throw new python.Error(`ValueError: not enough values to unpack (expected ${target.value.length}, actual ${value.length}).`);
                        }
                        for (let i = 0; i < value.length; i++) {
                            context.set(target.elts[i].id, value[i]);
                        }
                        return undefined;
                    }
                }
                break;
            }
            case 'List': {
                return expr.elts.map((expr) => this.expression(expr, context));
            }
            case 'Constant': {