1 files changed, 55 insertions, 0 deletions
diff --git a/types.go b/types.go
new file mode 100644
index 0000000..ea8d4c4
--- /dev/null
+++ b/types.go
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+// Copyright (c) 2020 Alexander Kiryukhin <a.kiryukhin@mail.ru>
+
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package executor
+
+import (
+	"errors"
+)
+
+// ErrInvalidExpression invalid expression error
+// ErrInvalidParenthesis invalid parenthesis error
+var (
+	ErrInvalidExpression  = errors.New("invalid expression")
+	ErrInvalidParenthesis = errors.New("invalid parenthesis")
+)
+
+type tokenType int
+
+const (
+	literalType tokenType = iota
+	variableType
+	operatorType
+	leftParenthesisType
+	rightParenthesisType
+	functionType
+	funcSep
+	eof
+)
+
+type token struct {
+	Type   tokenType
+	SValue string
+	FValue float64
+}
+
+func newToken(ttype tokenType, SValue string, FValue float64) *token {
+	return &token{Type: ttype, SValue: SValue, FValue: FValue}
+}