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+footer: Topics in Compilers and Concurrency · Julius Fischer · 10.06.2026
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+---
+
+# Destination Calculus:
+## A Linear 𝜆-Calculus for Purely Functional Memory Writes
+### Topics in Compiler and Concurrency
+#### Julius Fischer
+
+###### 10. Juni 2026
+
+---
+# What are Destinations?
+- Destination Passing Style
+    - Imperative
+    - Function takes destination instead of returning structure
+---
+# Example in C
+```
+int* vec_add(int v1[], int v2[], int size) {
+    int* res =  malloc(size * sizeof(int));
+    for (int i = 0; i < size; i++) {
+        res[i] = v1[i] + v2[i];
+    }
+    return res;
+}
+```
+- Add an 'out parameter'
+```
+void dps_vec_add(int res[], int v1[], int v2[], int size) {
+    for (int i = 0; i < size; i++) {
+        res[i] = v1[i] + v2[i];
+    }
+}
+```
+---
+# Motivation for DPS
+- Typical functional map implementation
+```
+map f (x:xs) = (f x : map f xs1)
+> (f x : map f xs) 
+> (map f x1 : (f x2 : map f xs2)) 
+> ...
+```
+- Not tail recursive 
+    - Performance issue
+    - Inefficient stack growth
+```
+map f (x:xs) dest = map f xs (push dest (f x))
+> map f xs1 (push dest (f x1))
+> map f xs2 (push dest (f x2))
+```
+--- 
+# DPS in functional languages
+- Just add pointers to mutable data?
+    - $Int \mapsto Int \mapsto Int \mapsto \textcolor{red}{T}$
+    - $\textcolor{red}{T *}\mapsto Int \mapsto Int \mapsto Int \mapsto Void$
+
+---
+# Destination Calculus
+- It's 
+
+--- 
+# Referenes