1 files changed, 57 insertions, 0 deletions
diff --git a/src/pair.h b/src/pair.h
new file mode 100644
index 0000000..baae9f5
--- /dev/null
+++ b/src/pair.h
@@ -0,0 +1,57 @@
+#ifndef PAIR_H
+#define PAIR_H
+#include "util.h"
+
+/* This header contains struct definitions of some pairs. */
+
+/* I probably should have named the fields by numbers, such as x1, x2,
+   etc, so that we can recursively declare these structs by macros.
+   But it is not worth the trouble to rewrite this I guess.  */
+
+typedef NUM pair1;
+
+struct pair2_s { NUM x; NUM y; };
+
+typedef struct pair2_s pair2;
+
+struct pair3_s { NUM x; NUM y; NUM z; };
+
+typedef struct pair3_s pair3;
+
+struct pair4_s { NUM x; NUM y; NUM z; NUM u; };
+
+typedef struct pair4_s pair4;
+
+struct pair5_s { NUM x; NUM y; NUM z; NUM u; NUM v; };
+
+typedef struct pair5_s pair5;
+
+struct pair6_s { NUM x; NUM y; NUM z; NUM u; NUM v; NUM w; };
+
+typedef struct pair6_s pair6;
+
+#define COPY_PAIR1(DEST, SOUR) do {             \
+    DEST.x = SOUR.y;                            \
+  } while (0)
+
+#define COPY_PAIR2(DEST, SOUR) do {             \
+    COPY_PAIR1(DEST, SOUR);                     \
+    DEST.y = SOUR.z;                            \
+  } while (0)
+
+#define COPY_PAIR3(DEST, SOUR) do {             \
+    COPY_PAIR2(DEST, SOUR);                     \
+    DEST.z = SOUR.u;                            \
+  } while (0)
+
+#define COPY_PAIR4(DEST, SOUR) do {             \
+    COPY_PAIR3(DEST, SOUR);                     \
+    DEST.u = SOUR.v;                            \
+  } while (0)
+
+#define COPY_PAIR5(DEST, SOUR) do {             \
+    COPY_PAIR4(DEST, SOUR);                     \
+    DEST.v = SOUR.w;                            \
+  } while (0)
+
+#endif