This book constitutes the thoroughly refereed revised selected papers of the 13th International Symposium on Trends in Functional Programming, TFP 2012, held in St Andrews, Scotland, UK in June 2012. The 18 revised full papers included in this volume were carefully and selected from 49 submissions and are complemented with an invited paper. They cover various aspects of trends in functional programming.

Various aspects of trends in functional programming.- Combining deep and shallow embedding for EDSL.- The Blame theorem for a linear lambda calculus with type dynamic.- Higher-order size checking without subtyping.