SAS Language <!-- SPDX-License-Identifier: MIT -- <!-- Style rules derived from the @sasjs/core coding standards (https://github.com/sasjs/core), MIT licensed. -- Write idiomatic, production-quality SAS code. This skill covers the SAS language itself, independent of any framework. Scope - DATA step programming (SET/MERGE/BY, RETAIN, arrays, DO loops, hash objects, first./last. processing) - PROC SQL (joins, subqueries, views, pass-through with CONNECT TO) - Macro language (%macro/%mend, macro variables, %local/%global, conditional %IF logic, quoting functions %STR/%NRSTR/%BQUOTE, CALL SYMPUTX…