Completed arithmetic support, added initial incomplete code for intrinsic functions.

git-svn-id: https://shellinabox.googlecode.com/svn/trunk@108 0da03de8-d603-11dd-86c2-0f8696b7b6f9

demo/demo.js

@@ -514,14 +514,14 @@ Demo.prototype.expr = function() {
 };
 
 Demo.prototype.term = function() {
-  var value   = this.factor();
+  var value   = this.expn();
   while (value) {
     var token = this.tokens.peekToken();
     if (token != '*' && token != '/' && token != '\\') {
       break;
     }
     this.tokens.consume();
-    var v     = this.factor();
+    var v     = this.expn();
     if (!v) {
       return v;
     }
@@ -548,6 +548,37 @@ Demo.prototype.term = function() {
   return value;
 };
 
+Demo.prototype.expn = function() {
+  var value = this.intrinsic();
+  var token = this.tokens.peekToken();
+  if (token == '^') {
+    this.tokens.consume();
+    var exp = this.intrinsic();
+    if (exp == undefined || exp.val() == NaN) {
+      return exp;
+    }
+    if (value.type() != 1 /* TYPE_NUMBER */ || exp.type() != 1 /* TYPE_NUMBER */) {
+      return this.error("Numeric value expected");
+    }
+    var v   = Math.pow(value.val(), exp.val());
+    value   = new this.Value(1 /* TYPE_NUMBER */, '' + v, v);
+  }
+  return value;
+};
+
+Demo.prototype.intrinsic = function() {
+  var token = this.tokens.peekToken();
+  if (token.match(/^(?:ABS|ASC|ATN|CHR\$|COS|EXP|INT|LEN|LOG|POS|RND|SGN|SIN|SPC|SQR|STR\$|TAN|VAL)$/)) {
+    return this.error('Unimplemented');
+  } else if (token.match(/^(?:LEFT\$|RIGHT\$)$/)) {
+    return this.error('Unimplemented');
+  } else if (token == 'MID$') {
+    return this.error('Unimplemented');
+  } else {
+    return this.factor();
+  }
+};
+
 Demo.prototype.factor = function() {
   var token    = this.tokens.nextToken();
   if (!token) {
@@ -555,6 +586,13 @@ Demo.prototype.factor = function() {
   }
 
   var value    = undefined;
+  if (token == '(') {
+    value      = this.expr();
+    token      = this.tokens.nextToken();
+    if (token != ')' && value != undefined) {
+      return this.error('")" expected');
+    }
+  } else {
     var str;
     if ((str = token.match(/^"(.*)"/)) != null) {
       value    = new this.Value(0 /* TYPE_STRING */, str[1], str[1]);
@@ -572,6 +610,7 @@ Demo.prototype.factor = function() {
     } else {
       return this.error();
     }
+  }
 
   return value;
 };
@@ -641,12 +680,17 @@ Demo.prototype.Tokens.prototype.peekToken = function() {
       }
     } else if (token >= 'A' && token <= 'Z' ||
                token >= 'a' && token <= 'z') {
+      token     = tokens.match(/^(?:CHR\$|STR\$|LEFT\$|RIGHT\$|MID\$)/i);
+      if (token) {
+        token   = token[0].toUpperCase();
+      } else {
         token   = tokens.match(/^[A-Za-z][A-Za-z0-9_]*/);
         if (!token) {
           token = undefined;
         } else {
           token = token[0].toUpperCase();
         }
+      }
     } else {
       token     = '';
     }

demo/demo.jspp

@@ -514,14 +514,14 @@ Demo.prototype.expr = function() {
 };
 
 Demo.prototype.term = function() {
-  var value   = this.factor();
+  var value   = this.expn();
   while (value) {
     var token = this.tokens.peekToken();
     if (token != '*' && token != '/' && token != '\\') {
       break;
     }
     this.tokens.consume();
-    var v     = this.factor();
+    var v     = this.expn();
     if (!v) {
       return v;
     }
@@ -548,6 +548,37 @@ Demo.prototype.term = function() {
   return value;
 };
 
+Demo.prototype.expn = function() {
+  var value = this.intrinsic();
+  var token = this.tokens.peekToken();
+  if (token == '^') {
+    this.tokens.consume();
+    var exp = this.intrinsic();
+    if (exp == undefined || exp.val() == NaN) {
+      return exp;
+    }
+    if (value.type() != TYPE_NUMBER || exp.type() != TYPE_NUMBER) {
+      return this.error("Numeric value expected");
+    }
+    var v   = Math.pow(value.val(), exp.val());
+    value   = new this.Value(TYPE_NUMBER, '' + v, v);
+  }
+  return value;
+};
+
+Demo.prototype.intrinsic = function() {
+  var token = this.tokens.peekToken();
+  if (token.match(/^(?:ABS|ASC|ATN|CHR\$|COS|EXP|INT|LEN|LOG|POS|RND|SGN|SIN|SPC|SQR|STR\$|TAN|VAL)$/)) {
+    return this.error('Unimplemented');
+  } else if (token.match(/^(?:LEFT\$|RIGHT\$)$/)) {
+    return this.error('Unimplemented');
+  } else if (token == 'MID$') {
+    return this.error('Unimplemented');
+  } else {
+    return this.factor();
+  }
+};
+
 Demo.prototype.factor = function() {
   var token    = this.tokens.nextToken();
   if (!token) {
@@ -555,6 +586,13 @@ Demo.prototype.factor = function() {
   }
 
   var value    = undefined;
+  if (token == '(') {
+    value      = this.expr();
+    token      = this.tokens.nextToken();
+    if (token != ')' && value != undefined) {
+      return this.error('")" expected');
+    }
+  } else {
     var str;
     if ((str = token.match(/^"(.*)"/)) != null) {
       value    = new this.Value(TYPE_STRING, str[1], str[1]);
@@ -572,6 +610,7 @@ Demo.prototype.factor = function() {
     } else {
       return this.error();
     }
+  }
 
   return value;
 };
@@ -641,12 +680,17 @@ Demo.prototype.Tokens.prototype.peekToken = function() {
       }
     } else if (token >= 'A' && token <= 'Z' ||
                token >= 'a' && token <= 'z') {
+      token     = tokens.match(/^(?:CHR\$|STR\$|LEFT\$|RIGHT\$|MID\$)/i);
+      if (token) {
+        token   = token[0].toUpperCase();
+      } else {
         token   = tokens.match(/^[A-Za-z][A-Za-z0-9_]*/);
         if (!token) {
           token = undefined;
         } else {
           token = token[0].toUpperCase();
         }
+      }
     } else {
       token     = '';
     }