Extract variable management, move into `state` package

7 files changed, 56 insertions, 27 deletions

diff --git a/source/machine.d b/source/machine.d
index 61d20cb..fe41701 100644
--- a/source/machine.d
+++ b/source/machine.d
@@ -6,10 +6,10 @@ import std.variant;
 import std.stdio          : writeln;
 import std.container.util : make;
 
-import definition = base.definition;
 import primitives = primitives.eval;
+import definition = state.definition;
 
-import base.stack;
+import state.stack;
 
 void process(string value) {
 	auto buffer = make!(Stack!Token)(toToken(value));
diff --git a/source/primitives/conditional.d b/source/primitives/conditional.d
index 5dc0fa5..fd101bd 100644
--- a/source/primitives/conditional.d
+++ b/source/primitives/conditional.d
@@ -4,7 +4,7 @@ import std.variant;
 import std.typecons;
 import std.container : DList;
 
-import base.stack;
+import state.stack;
 
 bool handle(string word) {
 	switch ( word ) {
diff --git a/source/primitives/core.d b/source/primitives/core.d
index cae577b..75783ed 100644
--- a/source/primitives/core.d
+++ b/source/primitives/core.d
@@ -2,12 +2,10 @@ module primitives.core;
 
 import std.stdio;
 
-import base.stack;
+import state.stack;
 
 bool handle(string word) {
 	switch ( word ) {
-		case     "$"     : binary_op_variable_bind;      break;
-		case     "@"     : unary_op_variable_resolve;    break;
 		case     "+"     : binary_op_add;                break;
 		case     "*"     : binary_op_multiply;           break;
 		case     "/"     : binary_op_divide;             break;
@@ -28,22 +26,6 @@ bool handle(string word) {
 
 private {
 
-Token[string] variables;
-
-void binary_op_variable_bind() {
-	string name     = stack.pop.get!string;
-	Token  value    = stack.pop;
-	variables[name] = value;
-}
-
-void unary_op_variable_resolve() {
-	string name = stack.pop.get!string;
-
-	if ( name in variables ) {
-		stack.push(variables[name]);
-	}
-}
-
 void binary_op_add() {
 	int b = stack.pop.get!int;
 	int a = stack.pop.get!int;
diff --git a/source/primitives/eval.d b/source/primitives/eval.d
index fc5938e..a18e897 100644
--- a/source/primitives/eval.d
+++ b/source/primitives/eval.d
@@ -2,10 +2,12 @@ module primitives.eval;
 
 import std.variant;
 
-import base.stack;
+import state.stack;
+
+import definition  = state.definition;
+import variable    = state.variable;
 
 import core        = primitives.core;
-import definition  = base.definition;
 import conditional = primitives.conditional;
 
 bool evaluate(Token token) {
@@ -17,6 +19,10 @@ bool evaluate(Token token) {
 		return true;
 	}
 
+	if ( variable.handle(token) ) {
+		return true;
+	}
+
 	return token.visit!(
 		(int    value) => false,
 		(bool   value) => false,
diff --git a/source/base/definition.d b/source/state/definition.d
index d37ad20..ab100d5 100644
--- a/source/base/definition.d
+++ b/source/state/definition.d
@@ -1,4 +1,4 @@
-module base.definition;
+module state.definition;
 
 import std.string;
 import std.variant;
@@ -6,7 +6,7 @@ import std.typecons;
 
 import std.container : DList;
 
-import base.stack;
+import state.stack;
 
 alias Words = Stack!Token[string];
 
diff --git a/source/base/stack.d b/source/state/stack.d
index c6e1a59..3c6230f 100644
--- a/source/base/stack.d
+++ b/source/state/stack.d
@@ -1,4 +1,4 @@
-module base.stack;
+module state.stack;
 
 import std.conv;
 import std.string;
diff --git a/source/state/variable.d b/source/state/variable.d
new file mode 100644
index 0000000..f77e207
--- /dev/null
+++ b/source/state/variable.d
@@ -0,0 +1,41 @@
+module state.variable;
+
+import std.variant;
+
+import state.stack;
+
+bool handle(string word) {
+	switch ( word ) {
+		case "$" : binary_op_variable_bind;   return true;
+		case "@" : unary_op_variable_resolve; return true;
+		default  :                            return false;
+	}
+}
+
+bool handle(Token token) {
+	return token.visit!(
+		(int        ) => false,
+		(bool       ) => false,
+		(string word) => handle(word)
+	);
+}
+
+private {
+
+Token[string] variables;
+
+void binary_op_variable_bind() {
+	string name     = stack.pop.get!string;
+	Token  value    = stack.pop;
+	variables[name] = value;
+}
+
+void unary_op_variable_resolve() {
+	string name = stack.pop.get!string;
+
+	if ( name in variables ) {
+		stack.push(variables[name]);
+	}
+}
+
+}