More closure tests.

test.c

@@ -425,6 +425,10 @@ double clo2(void *context, double a, double b) {
     return a + b;
 }
 
+double cell(void *context, double a) {
+    double *c = context;
+    return c[(int)a];
+}
 
 void test_closure() {
 
@@ -432,6 +436,7 @@ void test_closure() {
         {"c0", clo0, TE_CLOSURE0},
         {"c1", clo1, TE_CLOSURE1},
         {"c2", clo2, TE_CLOSURE2},
+        {"cell", cell, TE_CLOSURE1},
     };
 
     test_case cases[] = {
@@ -453,6 +458,26 @@ void test_closure() {
         lfequal(te_eval_closure(ex, &extra), answer + extra);
         te_free(ex);
     }
+
+
+    double c[] = {5,6,7,8,9};
+    test_case cases2[] = {
+        {"cell 0", 5},
+        {"cell 1", 6},
+        {"cell 0 + cell 1", 11},
+        {"cell 1 * cell 3 + cell 4", 57},
+    };
+
+    for (i = 0; i < sizeof(cases2) / sizeof(test_case); ++i) {
+        const char *expr = cases2[i].expr;
+        const double answer = cases2[i].answer;
+
+        int err;
+        te_expr *ex = te_compile(expr, lookup, sizeof(lookup)/sizeof(te_variable), &err);
+        lok(ex);
+        lfequal(te_eval_closure(ex, c), answer);
+        te_free(ex);
+    }
 }