From d83fa29bb4963a5094febaf4725335b17fbf4adb Mon Sep 17 00:00:00 2001
From: = <=>
Date: Sun, 10 May 2020 07:27:59 +0100
Subject: [PATCH] Began `cat` code and added `spent` demo func

---
 src/object.c   | 31 +++++++++++++++++++++++++++++++
 src/object.h   |  5 ++++-
 src/pebblisp.c | 34 ++++++++++++++++++++++++++++++++++
 src/tokens.c   |  9 +++++++++
 4 files changed, 78 insertions(+), 1 deletion(-)

diff --git a/src/object.c b/src/object.c
index b26e1dc..2a3ab20 100644
--- a/src/object.c
+++ b/src/object.c
@@ -238,6 +238,8 @@ char* stringObj(char *dest, const Object *obj)
         snprintf(dest, RESULT_LENGTH, "%s", obj->number ? "T" : "F");
     } else if(t == TYPE_ERROR) {
         snprintf(dest, RESULT_LENGTH, "E%d", obj->err);
+    } else if(t == TYPE_STRING) {
+        snprintf(dest, RESULT_LENGTH, "%s", obj->string);
     } else if(t == TYPE_LIST) {
         stringList(dest, obj);
     } else {
@@ -324,6 +326,12 @@ void cleanObject(Object *target)
         free(target->lambda);
     } else if(t == TYPE_LIST) {
         deleteList(target);
+    } else if(t == TYPE_STRING) {
+        // TODO Why does this break?
+        // Probably multiple objects referencing the same string
+
+        // free(target->string);
+        // target->string = NULL;
     }
     target->forward = NULL;
 }
@@ -437,6 +445,29 @@ inline Object lambdaObject()
     return o;
 }
 
+// Skips first char! Assumed to be '"'
+inline Object objFromSlice(const char *string, int len)
+{
+    Object o = newObject(TYPE_STRING);
+    o.string = calloc(sizeof(char), len);
+    for(int i = 0; i < len - 1; i++) {
+        o.string[i] = string[i + 1];
+    }
+    o.string[len - 1] = '\0';
+    return o;
+}
+
+// inline Object objFromString(const char *string)
+// {
+//     Object o = newObject(TYPE_STRING);
+//     o.string = calloc(strlen(string) + 1);
+//     for(int i = 0; i < len - 1; i++) {
+//         o.string[i] = string[i];
+//     }
+//     o.string[len - 1] = '\0';
+//     return o;
+// }
+
 inline Object constructLambda(const Object *params, const Object *body)
 {
     if(!params || !body)
diff --git a/src/object.h b/src/object.h
index cf2161e..99477fc 100644
--- a/src/object.h
+++ b/src/object.h
@@ -63,13 +63,14 @@ typedef enum Type {
     TYPE_FUNC,
     TYPE_SYMBOL,
     TYPE_LAMBDA,
+    TYPE_STRING,
     TYPE_ERROR
 } Type;
 
 typedef struct Object Object;
 struct Lambda;
-
 struct Environment;
+struct Slice;
 
 struct Object {
     Type type;
@@ -78,6 +79,7 @@ struct Object {
         int number;
         Object *list;
         char name[MAX_TOK_LEN];
+        char *string;
         Object (*func)(Object, Object, struct Environment *env);
         struct Lambda *lambda; // Maybe better as not a pointer?
         enum errorCode err;
@@ -118,6 +120,7 @@ Object listObject();
 Object startList(const Object start);
 Object lambdaObject();
 Object symbolObject();
+Object objFromSlice(const char *string, int len);
 Object boolObject(int b);
 Object numberObject(int num);
 Object errorObject(enum errorCode err);
diff --git a/src/pebblisp.c b/src/pebblisp.c
index 7107b9f..fdcdef2 100644
--- a/src/pebblisp.c
+++ b/src/pebblisp.c
@@ -106,6 +106,8 @@ Object parseAtom(struct Slice *s)
     } else if (s->text[0] == 'F' && s->length == 1) {
         return boolObject(0);
 
+    } else if (s->text[0] == '"') {
+        return objFromSlice(s->text, s->length);
     } else {
         Object o = symbolObject();
         copySlice(o.name, s);
@@ -234,6 +236,7 @@ Object eval(const Object *obj, struct Environment *env)
     switch(obj->type) {
         case TYPE_NUMBER:
         case TYPE_BOOL:
+        case TYPE_STRING:
             return *obj; // Return as is
 
         case TYPE_SYMBOL:
@@ -353,6 +356,25 @@ void printEnv(struct Environment *env)
     }
 }
 
+Object catObjects(const Object obj1, const Object obj2, struct Environment *env)
+{
+    const Object evalObj1 = eval(&obj1, env);
+    const Object evalObj2 = eval(&obj2, env);
+
+    char str1[100] = "";
+    char str2[100] = "";
+    stringObj(str1, &evalObj1);
+    stringObj(str2, &evalObj2);
+    int length = strlen(str1) + strlen(str2) + 1;
+
+    Object o = newObject(TYPE_STRING);
+    o.string = calloc(sizeof(char), length);
+    strcat(o.string, str1);
+    strcat(o.string, str2);
+
+    return o;
+}
+
 Object _basicOp(const Object *obj1, const Object *obj2, const char op)
 {
     const int n1 = obj1->number;
@@ -367,6 +389,8 @@ Object _basicOp(const Object *obj1, const Object *obj2, const char op)
             return numberObject(n1 * n2);
         case '/':
             return numberObject(n1 / n2);
+        case '%':
+            return numberObject(n1 % n2);
 
         case '=':
             return boolObject(n1 == n2);
@@ -417,6 +441,7 @@ bopf(add, '+');
 bopf(sub, '-');
 bopf(mul, '*');
 bopf(dvi, '/');
+bopf(mod, '%');
 bopf(equ, '=');
 bopf(gth, '>');
 bopf(lth, '<');
@@ -455,13 +480,22 @@ struct Environment defaultEnv() {
     addFunc("-", &sub, &e);
     addFunc("*", &mul, &e);
     addFunc("/", &dvi, &e);
+    addFunc("%", &mod, &e);
     addFunc("=", &equ, &e);
     addFunc(">", &gth, &e);
     addFunc("<", &lth, &e);
     addFunc("len", &len, &e);
+    addFunc("cat", &catObjects, &e);
+
     parseEval("(def max (fn (a b) (if (> a b) a b)))", &e);
     parseEval("(def min (fn (a b) (if (< a b) a b)))", &e);
     parseEval("(def ad (fn (a) (if (> a 10) a (ad (* 10 a) ))))", &e);
+    parseEval("(def spent (fn (a) \
+                (cat \"Tip: $\" (/ a 5) \".\" \
+                  (/ (* 100 (% a 5)) 5) \
+                ) \
+              ))", 
+              &e);
 
     return e;
 }
diff --git a/src/tokens.c b/src/tokens.c
index c8eb88d..bef850d 100644
--- a/src/tokens.c
+++ b/src/tokens.c
@@ -75,6 +75,15 @@ struct Slice *nf_tokenize(const char *input)
             slice++;
             i++;
 
+        } else if(input[i] == '"') {
+            slices[slice].text = &input[i];
+            int l = 1;
+            while(input[++i] != '"') {
+                l++;
+            }
+            i++;
+            slices[slice].length = l;
+            slice++;
         } else {
             slices[slice].text = &input[i];
             int l = 1;