Drafting ProductStatement

mmql/engine/lexer.go

@@ -135,6 +135,54 @@ func ( this *Lexer ) ReadDecimal() ( f float64, err error ) {
     return
 }
 
+func ( this *Lexer ) ReadKeyword( Keyword string ) ( err error ) {
+
+    reader := this.reader
+    kReader := strings.NewReader( Keyword )
+
+    var b strings.Builder
+    for {
+        r, _, _err := reader.ReadRune()
+        err = _err
+        if err != nil {
+            if err == io.EOF {
+                if 0 < b.Len() {
+                    err = nil
+                } else {
+                    err = fmt.Errorf( "Nothing left to read" )
+                    return
+                }
+            }
+            break
+        }
+
+        if strings.ContainsRune( K_SPACES, r ) && b.Len() == 0 {
+            continue
+        }
+
+        k, _, _err := kReader.ReadRune()
+        if _err != nil {
+            if _err != io.EOF {
+                err = _err
+            } else {
+                err = nil
+            }
+            return
+        }
+
+        if k != r {
+            err = fmt.Errorf(
+                "Expected \"%s\", got \"%s\"",
+                Keyword,
+                this.ReadUntilNot( K_STATEMENT_CHARS, true, r ),
+            )
+            return
+        }
+        b.WriteRune( r )
+    }
+    return
+}
+
 func ( this *Lexer ) ReadAlpha() ( s string, err error ) {
     reader := this.reader
 

mmql/engine/lexer_test.go

@@ -116,4 +116,15 @@ func TestAlpha( t *testing.T ) {
             t.Errorf( "Expected error for %s, got %s", v, f )
         }
     }
+
+    lexer.SetReader( strings.NewReader( "abcd efgh" ) )
+    f, err := lexer.ReadAlpha()
+    f, err = lexer.ReadAlpha()
+    if err != nil {
+        t.Errorf( "Expected string for \"efgh\", got %s", err )
+    }
+
+    if f != "efgh" {
+        t.Errorf( "Expected \"efgh\", got %s", f )
+    }
 }

mmql/statements/actions/buy.go

@@ -18,10 +18,11 @@ THEN OPT EXPECT: FOR EVERY
     THEN EXPECT: [SOLD|BOUGHT] FROM [ExchangeType]
 */
 
-func BuyStatement( lexer *engine.Lexer ) ( stmtd.IStatement, error ) {
+func BuyStatement( lexer *engine.Lexer ) ( istmt stmtd.IStatement, err error ) {
     orderStmt := stmtd.OrderStatement{}
     orderStmt.Action = "BUY"
 
+    // AmountStatement
     readAmount := engine.LexerExpect{
         Statements: true,
         Keywords: false,
@@ -32,10 +33,30 @@ func BuyStatement( lexer *engine.Lexer ) ( stmtd.IStatement, error ) {
 
     amountStmt, err := lexer.ReadStatement( &readAmount )
     if err != nil {
-        return nil, err
+        return
     }
     orderStmt.For( amountStmt )
 
-    var istmt stmtd.IStatement = orderStmt
+    // OF
-    return istmt, err
+    err = lexer.ReadKeyword( "OF" )
+    if err != nil {
+        return
+    }
+
+    // ProductStatement
+    readProduct := engine.LexerExpect{
+        Statements: true,
+        Keywords: false,
+        Brackets: false,
+        Quotes: false,
+        Key: "PRODUCT",
+    }
+    productStmt, err := lexer.ReadStatement( &readProduct )
+    if err != nil {
+        return
+    }
+    orderStmt.Product( productStmt )
+
+    istmt = orderStmt
+    return
 }

mmql/statements/actions/buy_test.go

@@ -12,6 +12,7 @@ func TestBuyStatement( t *testing.T ) {
     supportedStmts := map[string] func( *engine.Lexer ) ( stmtd.IStatement, error ) {
         "BUY": BuyStatement,
         "AMOUNT": AmountStatement,
+        "PRODUCT": ProductStatement,
     }
     lexer.SupportedStmts = &supportedStmts
 

mmql/statements/actions/product.go

@@ -0,0 +1,26 @@
+package actions
+
+import (
+    // "fmt"
+    engine "github.com/tgckpg/mmqlengine/mmql/engine"
+    stmtd "github.com/tgckpg/mmqlengine/mmql/statements"
+)
+
+/*
+EXPECT: [NAME]
+OR
+EXPECT: [FUNCTION]( ...params )
+*/
+
+func ProductStatement( lexer *engine.Lexer ) ( istmt stmtd.IStatement, err error ) {
+    stmt := stmtd.ProductStatement{}
+
+    name, err := lexer.ReadAlpha()
+    if err != nil {
+        return
+    }
+    stmt.Name = name
+
+    istmt = stmt
+    return
+}

mmql/statements/types.go

@@ -25,8 +25,16 @@ type AmountStatement struct {
     Unit string
 }
 
+type ProductStatement struct {
+    IStatement
+    Name string
+}
+
 type IActionStatement interface { }
 
+
+
+
 type OrderStatement struct {
     IStatement
     IActionStatement
@@ -35,3 +43,6 @@ type OrderStatement struct {
 
 func ( this *OrderStatement ) For( stmt IStatement ) {
 }
+
+func ( this *OrderStatement ) Product( stmt IStatement ) {
+}