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diff --git a/LICENSE b/LICENSE
new file mode 100644
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--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,373 @@
+Mozilla Public License Version 2.0
+==================================
+
+1. Definitions
+--------------
+
+1.1. "Contributor"
+    means each individual or legal entity that creates, contributes to
+    the creation of, or owns Covered Software.
+
+1.2. "Contributor Version"
+    means the combination of the Contributions of others (if any) used
+    by a Contributor and that particular Contributor's Contribution.
+
+1.3. "Contribution"
+    means Covered Software of a particular Contributor.
+
+1.4. "Covered Software"
+    means Source Code Form to which the initial Contributor has attached
+    the notice in Exhibit A, the Executable Form of such Source Code
+    Form, and Modifications of such Source Code Form, in each case
+    including portions thereof.
+
+1.5. "Incompatible With Secondary Licenses"
+    means
+
+    (a) that the initial Contributor has attached the notice described
+        in Exhibit B to the Covered Software; or
+
+    (b) that the Covered Software was made available under the terms of
+        version 1.1 or earlier of the License, but not also under the
+        terms of a Secondary License.
+
+1.6. "Executable Form"
+    means any form of the work other than Source Code Form.
+
+1.7. "Larger Work"
+    means a work that combines Covered Software with other material, in
+    a separate file or files, that is not Covered Software.
+
+1.8. "License"
+    means this document.
+
+1.9. "Licensable"
+    means having the right to grant, to the maximum extent possible,
+    whether at the time of the initial grant or subsequently, any and
+    all of the rights conveyed by this License.
+
+1.10. "Modifications"
+    means any of the following:
+
+    (a) any file in Source Code Form that results from an addition to,
+        deletion from, or modification of the contents of Covered
+        Software; or
+
+    (b) any new file in Source Code Form that contains any Covered
+        Software.
+
+1.11. "Patent Claims" of a Contributor
+    means any patent claim(s), including without limitation, method,
+    process, and apparatus claims, in any patent Licensable by such
+    Contributor that would be infringed, but for the grant of the
+    License, by the making, using, selling, offering for sale, having
+    made, import, or transfer of either its Contributions or its
+    Contributor Version.
+
+1.12. "Secondary License"
+    means either the GNU General Public License, Version 2.0, the GNU
+    Lesser General Public License, Version 2.1, the GNU Affero General
+    Public License, Version 3.0, or any later versions of those
+    licenses.
+
+1.13. "Source Code Form"
+    means the form of the work preferred for making modifications.
+
+1.14. "You" (or "Your")
+    means an individual or a legal entity exercising rights under this
+    License. For legal entities, "You" includes any entity that
+    controls, is controlled by, or is under common control with You. For
+    purposes of this definition, "control" means (a) the power, direct
+    or indirect, to cause the direction or management of such entity,
+    whether by contract or otherwise, or (b) ownership of more than
+    fifty percent (50%) of the outstanding shares or beneficial
+    ownership of such entity.
+
+2. License Grants and Conditions
+--------------------------------
+
+2.1. Grants
+
+Each Contributor hereby grants You a world-wide, royalty-free,
+non-exclusive license:
+
+(a) under intellectual property rights (other than patent or trademark)
+    Licensable by such Contributor to use, reproduce, make available,
+    modify, display, perform, distribute, and otherwise exploit its
+    Contributions, either on an unmodified basis, with Modifications, or
+    as part of a Larger Work; and
+
+(b) under Patent Claims of such Contributor to make, use, sell, offer
+    for sale, have made, import, and otherwise transfer either its
+    Contributions or its Contributor Version.
+
+2.2. Effective Date
+
+The licenses granted in Section 2.1 with respect to any Contribution
+become effective for each Contribution on the date the Contributor first
+distributes such Contribution.
+
+2.3. Limitations on Grant Scope
+
+The licenses granted in this Section 2 are the only rights granted under
+this License. No additional rights or licenses will be implied from the
+distribution or licensing of Covered Software under this License.
+Notwithstanding Section 2.1(b) above, no patent license is granted by a
+Contributor:
+
+(a) for any code that a Contributor has removed from Covered Software;
+    or
+
+(b) for infringements caused by: (i) Your and any other third party's
+    modifications of Covered Software, or (ii) the combination of its
+    Contributions with other software (except as part of its Contributor
+    Version); or
+
+(c) under Patent Claims infringed by Covered Software in the absence of
+    its Contributions.
+
+This License does not grant any rights in the trademarks, service marks,
+or logos of any Contributor (except as may be necessary to comply with
+the notice requirements in Section 3.4).
+
+2.4. Subsequent Licenses
+
+No Contributor makes additional grants as a result of Your choice to
+distribute the Covered Software under a subsequent version of this
+License (see Section 10.2) or under the terms of a Secondary License (if
+permitted under the terms of Section 3.3).
+
+2.5. Representation
+
+Each Contributor represents that the Contributor believes its
+Contributions are its original creation(s) or it has sufficient rights
+to grant the rights to its Contributions conveyed by this License.
+
+2.6. Fair Use
+
+This License is not intended to limit any rights You have under
+applicable copyright doctrines of fair use, fair dealing, or other
+equivalents.
+
+2.7. Conditions
+
+Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted
+in Section 2.1.
+
+3. Responsibilities
+-------------------
+
+3.1. Distribution of Source Form
+
+All distribution of Covered Software in Source Code Form, including any
+Modifications that You create or to which You contribute, must be under
+the terms of this License. You must inform recipients that the Source
+Code Form of the Covered Software is governed by the terms of this
+License, and how they can obtain a copy of this License. You may not
+attempt to alter or restrict the recipients' rights in the Source Code
+Form.
+
+3.2. Distribution of Executable Form
+
+If You distribute Covered Software in Executable Form then:
+
+(a) such Covered Software must also be made available in Source Code
+    Form, as described in Section 3.1, and You must inform recipients of
+    the Executable Form how they can obtain a copy of such Source Code
+    Form by reasonable means in a timely manner, at a charge no more
+    than the cost of distribution to the recipient; and
+
+(b) You may distribute such Executable Form under the terms of this
+    License, or sublicense it under different terms, provided that the
+    license for the Executable Form does not attempt to limit or alter
+    the recipients' rights in the Source Code Form under this License.
+
+3.3. Distribution of a Larger Work
+
+You may create and distribute a Larger Work under terms of Your choice,
+provided that You also comply with the requirements of this License for
+the Covered Software. If the Larger Work is a combination of Covered
+Software with a work governed by one or more Secondary Licenses, and the
+Covered Software is not Incompatible With Secondary Licenses, this
+License permits You to additionally distribute such Covered Software
+under the terms of such Secondary License(s), so that the recipient of
+the Larger Work may, at their option, further distribute the Covered
+Software under the terms of either this License or such Secondary
+License(s).
+
+3.4. Notices
+
+You may not remove or alter the substance of any license notices
+(including copyright notices, patent notices, disclaimers of warranty,
+or limitations of liability) contained within the Source Code Form of
+the Covered Software, except that You may alter any license notices to
+the extent required to remedy known factual inaccuracies.
+
+3.5. Application of Additional Terms
+
+You may choose to offer, and to charge a fee for, warranty, support,
+indemnity or liability obligations to one or more recipients of Covered
+Software. However, You may do so only on Your own behalf, and not on
+behalf of any Contributor. You must make it absolutely clear that any
+such warranty, support, indemnity, or liability obligation is offered by
+You alone, and You hereby agree to indemnify every Contributor for any
+liability incurred by such Contributor as a result of warranty, support,
+indemnity or liability terms You offer. You may include additional
+disclaimers of warranty and limitations of liability specific to any
+jurisdiction.
+
+4. Inability to Comply Due to Statute or Regulation
+---------------------------------------------------
+
+If it is impossible for You to comply with any of the terms of this
+License with respect to some or all of the Covered Software due to
+statute, judicial order, or regulation then You must: (a) comply with
+the terms of this License to the maximum extent possible; and (b)
+describe the limitations and the code they affect. Such description must
+be placed in a text file included with all distributions of the Covered
+Software under this License. Except to the extent prohibited by statute
+or regulation, such description must be sufficiently detailed for a
+recipient of ordinary skill to be able to understand it.
+
+5. Termination
+--------------
+
+5.1. The rights granted under this License will terminate automatically
+if You fail to comply with any of its terms. However, if You become
+compliant, then the rights granted under this License from a particular
+Contributor are reinstated (a) provisionally, unless and until such
+Contributor explicitly and finally terminates Your grants, and (b) on an
+ongoing basis, if such Contributor fails to notify You of the
+non-compliance by some reasonable means prior to 60 days after You have
+come back into compliance. Moreover, Your grants from a particular
+Contributor are reinstated on an ongoing basis if such Contributor
+notifies You of the non-compliance by some reasonable means, this is the
+first time You have received notice of non-compliance with this License
+from such Contributor, and You become compliant prior to 30 days after
+Your receipt of the notice.
+
+5.2. If You initiate litigation against any entity by asserting a patent
+infringement claim (excluding declaratory judgment actions,
+counter-claims, and cross-claims) alleging that a Contributor Version
+directly or indirectly infringes any patent, then the rights granted to
+You by any and all Contributors for the Covered Software under Section
+2.1 of this License shall terminate.
+
+5.3. In the event of termination under Sections 5.1 or 5.2 above, all
+end user license agreements (excluding distributors and resellers) which
+have been validly granted by You or Your distributors under this License
+prior to termination shall survive termination.
+
+************************************************************************
+*                                                                      *
+*  6. Disclaimer of Warranty                                           *
+*  -------------------------                                           *
+*                                                                      *
+*  Covered Software is provided under this License on an "as is"       *
+*  basis, without warranty of any kind, either expressed, implied, or  *
+*  statutory, including, without limitation, warranties that the       *
+*  Covered Software is free of defects, merchantable, fit for a        *
+*  particular purpose or non-infringing. The entire risk as to the     *
+*  quality and performance of the Covered Software is with You.        *
+*  Should any Covered Software prove defective in any respect, You     *
+*  (not any Contributor) assume the cost of any necessary servicing,   *
+*  repair, or correction. This disclaimer of warranty constitutes an   *
+*  essential part of this License. No use of any Covered Software is   *
+*  authorized under this License except under this disclaimer.         *
+*                                                                      *
+************************************************************************
+
+************************************************************************
+*                                                                      *
+*  7. Limitation of Liability                                          *
+*  --------------------------                                          *
+*                                                                      *
+*  Under no circumstances and under no legal theory, whether tort      *
+*  (including negligence), contract, or otherwise, shall any           *
+*  Contributor, or anyone who distributes Covered Software as          *
+*  permitted above, be liable to You for any direct, indirect,         *
+*  special, incidental, or consequential damages of any character      *
+*  including, without limitation, damages for lost profits, loss of    *
+*  goodwill, work stoppage, computer failure or malfunction, or any    *
+*  and all other commercial damages or losses, even if such party      *
+*  shall have been informed of the possibility of such damages. This   *
+*  limitation of liability shall not apply to liability for death or   *
+*  personal injury resulting from such party's negligence to the       *
+*  extent applicable law prohibits such limitation. Some               *
+*  jurisdictions do not allow the exclusion or limitation of           *
+*  incidental or consequential damages, so this exclusion and          *
+*  limitation may not apply to You.                                    *
+*                                                                      *
+************************************************************************
+
+8. Litigation
+-------------
+
+Any litigation relating to this License may be brought only in the
+courts of a jurisdiction where the defendant maintains its principal
+place of business and such litigation shall be governed by laws of that
+jurisdiction, without reference to its conflict-of-law provisions.
+Nothing in this Section shall prevent a party's ability to bring
+cross-claims or counter-claims.
+
+9. Miscellaneous
+----------------
+
+This License represents the complete agreement concerning the subject
+matter hereof. If any provision of this License is held to be
+unenforceable, such provision shall be reformed only to the extent
+necessary to make it enforceable. Any law or regulation which provides
+that the language of a contract shall be construed against the drafter
+shall not be used to construe this License against a Contributor.
+
+10. Versions of the License
+---------------------------
+
+10.1. New Versions
+
+Mozilla Foundation is the license steward. Except as provided in Section
+10.3, no one other than the license steward has the right to modify or
+publish new versions of this License. Each version will be given a
+distinguishing version number.
+
+10.2. Effect of New Versions
+
+You may distribute the Covered Software under the terms of the version
+of the License under which You originally received the Covered Software,
+or under the terms of any subsequent version published by the license
+steward.
+
+10.3. Modified Versions
+
+If you create software not governed by this License, and you want to
+create a new license for such software, you may create and use a
+modified version of this License if you rename the license and remove
+any references to the name of the license steward (except to note that
+such modified license differs from this License).
+
+10.4. Distributing Source Code Form that is Incompatible With Secondary
+Licenses
+
+If You choose to distribute Source Code Form that is Incompatible With
+Secondary Licenses under the terms of this version of the License, the
+notice described in Exhibit B of this License must be attached.
+
+Exhibit A - Source Code Form License Notice
+-------------------------------------------
+
+  This Source Code Form is subject to the terms of the Mozilla Public
+  License, v. 2.0. If a copy of the MPL was not distributed with this
+  file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+If it is not possible or desirable to put the notice in a particular
+file, then You may include the notice in a location (such as a LICENSE
+file in a relevant directory) where a recipient would be likely to look
+for such a notice.
+
+You may add additional accurate notices of copyright ownership.
+
+Exhibit B - "Incompatible With Secondary Licenses" Notice
+---------------------------------------------------------
+
+  This Source Code Form is "Incompatible With Secondary Licenses", as
+  defined by the Mozilla Public License, v. 2.0.
diff --git a/README b/README
new file mode 100644
index 0000000..b6e03eb
--- /dev/null
+++ b/README
@@ -0,0 +1,37 @@
+# Elna programming language
+
+Elna compiles simple mathematical operations to machine code.
+The compiled program returns the result of the operation.
+
+## File extension
+
+.elna
+
+## Grammar PL/0
+
+program = block "." ;
+
+block = [ "const" ident "=" number {"," ident "=" number} ";"]
+        [ "var" ident {"," ident} ";"]
+        { "procedure" ident ";" block ";" } statement ;
+
+statement = [ ident ":=" expression | "call" ident 
+              | "?" ident | "!" expression 
+              | "begin" statement {";" statement } "end" 
+              | "if" condition "then" statement 
+              | "while" condition "do" statement ];
+
+condition = "odd" expression |
+            expression ("="|"#"|"<"|"<="|">"|">=") expression ;
+
+expression = [ "+"|"-"] term { ("+"|"-") term};
+
+term = factor {("*"|"/") factor};
+
+factor = ident | number | "(" expression ")";
+
+## Operations
+
+"!" - Write a line.
+"?" - Read user input.
+"odd" - The only function, returns whether a number is odd.
diff --git a/TODO b/TODO
new file mode 100644
index 0000000..b563094
--- /dev/null
+++ b/TODO
@@ -0,0 +1,5 @@
+# AST missing
+
+- Import
+- Record
+- Union
diff --git a/elna.cabal b/elna.cabal
new file mode 100644
index 0000000..7c27cbb
--- /dev/null
+++ b/elna.cabal
@@ -0,0 +1,33 @@
+cabal-version:      3.0
+name:               elna
+version:            0.1.0.0
+synopsis:
+    Elna programming language compiles simple mathematical operations to RISC-V code
+
+-- description:
+license:            MPL-2.0
+license-file:       LICENSE
+author:             Eugen Wissner
+maintainer:         belka@caraus.de
+-- copyright:
+category: Language
+build-type: Simple
+extra-doc-files: TODO README
+
+common warnings
+    ghc-options: -Wall
+
+executable elna
+    import:           warnings
+    main-is:          Main.hs
+    other-modules:
+        Language.Elna.AST
+        Language.Elna.Parser
+    default-extensions:
+        OverloadedStrings
+    build-depends:
+        base ^>=4.17.2.1,
+        megaparsec ^>= 9.6,
+        text ^>= 2.0
+    hs-source-dirs:   src
+    default-language: GHC2021
diff --git a/sample.elna b/sample.elna
new file mode 100644
index 0000000..2bf43dc
--- /dev/null
+++ b/sample.elna
@@ -0,0 +1,2 @@
+begin
+end.
diff --git a/src/Language/Elna/AST.hs b/src/Language/Elna/AST.hs
new file mode 100644
index 0000000..30c6627
--- /dev/null
+++ b/src/Language/Elna/AST.hs
@@ -0,0 +1,202 @@
+module Language.Elna.AST
+    ( ConstantDefinition(..)
+    , Expression(..)
+    , Identifier(..)
+    , Literal(..)
+    , ProcedureDeclaration(..)
+    , Program(..)
+    , Statement(..)
+    , VariableDeclaration(..)
+    , TypeName(..)
+    ) where
+
+import Data.Int (Int32)
+import Data.List (intercalate)
+import Data.Word (Word8)
+import Data.Text (Text)
+import qualified Data.Text as Text
+import Data.Char (chr)
+
+newtype Identifier = Identifier { unIdentifier :: Text }
+    deriving Eq
+
+instance Show Identifier
+  where
+    show (Identifier identifier) = Text.unpack identifier
+
+data TypeName
+    = NamedType Identifier
+    | PointerType TypeName
+    | ArrayType TypeName Int32
+    | ProcedureType [Parameter]
+    deriving Eq
+
+instance Show TypeName
+  where
+    show (NamedType typeName) = show typeName
+    show (PointerType typeName) = '^' : show typeName
+    show (ArrayType typeName elementCount) = concat
+        [show typeName, "[", show elementCount, "]"]
+    show (ProcedureType parameters) = "proc" <> showParameters parameters
+
+data Literal
+    = StringLiteral Text
+    | IntegerLiteral Int32
+    | CharacterLiteral Word8
+    | BooleanLiteral Bool
+    deriving Eq
+
+instance Show Literal
+  where
+    show (StringLiteral string) = Text.unpack
+        $ "\"" <> string <> "\""
+    show (IntegerLiteral integer) = show integer
+    show (CharacterLiteral character) =
+        '\'' : chr (fromEnum character) : ['\'']
+    show (BooleanLiteral boolean)
+        | boolean = "true"
+        | otherwise = "false"
+
+data Expression
+    = VariableExpression Identifier
+    | LiteralExpression Literal
+    | NegationExpression Expression
+    | NotExpression Expression
+    | ReferenceExpression Expression
+    | DereferenceExpression Expression
+    | SumExpression Expression Expression
+    | SubtractionExpression Expression Expression
+    | ProductExpression Expression Expression
+    | DivisionExpression Expression Expression
+    | EqualExpression Expression Expression
+    | NonEqualExpression Expression Expression
+    | LessExpression Expression Expression
+    | GreaterExpression Expression Expression
+    | LessOrEqualExpression Expression Expression
+    | GreaterOrEqualExpression Expression Expression
+    | IfExpression Expression Statement Statement
+    | LoopExpression Expression Statement
+    | FieldExpression Expression Identifier
+    deriving Eq
+
+instance Show Expression
+  where
+    show (VariableExpression variable) = show variable
+    show (LiteralExpression literal) = show literal
+    show (NegationExpression negation) = '-' : show negation
+    show (NotExpression negation) = "not " <> show negation
+    show (ReferenceExpression reference) = '@' : show reference
+    show (DereferenceExpression dereference) = show dereference <> "^"
+    show (SumExpression lhs rhs) = concat [show lhs, " + ", show rhs]
+    show (SubtractionExpression lhs rhs) = concat [show lhs, " - ", show rhs]
+    show (ProductExpression lhs rhs) = concat [show lhs, " * ", show rhs]
+    show (DivisionExpression lhs rhs) = concat [show lhs, " / ", show rhs]
+    show (EqualExpression lhs rhs) = concat [show lhs, " = ", show rhs]
+    show (NonEqualExpression lhs rhs) = concat [show lhs, " /= ", show rhs]
+    show (LessExpression lhs rhs) = concat [show lhs, " < ", show rhs]
+    show (GreaterExpression lhs rhs) = concat [show lhs, " > ", show rhs]
+    show (LessOrEqualExpression lhs rhs) = concat [show lhs, " <= ", show rhs]
+    show (GreaterOrEqualExpression lhs rhs) = concat [show lhs, " >= ", show rhs]
+    show (IfExpression condition if' else') = concat
+        [ "if ", show condition
+        , " then " <> show if'
+        , " else " <> show else'
+        ]
+    show (LoopExpression accumulator iteration) = concat
+        ["loop ", show accumulator, " do ", show iteration]
+    show (FieldExpression fieldExpression identifier) =
+        show fieldExpression <> "." <> show identifier
+
+data Statement
+    = LetStatement Identifier TypeName Expression
+    | CompoundStatement [Statement]
+    | CallStatement Identifier [Expression]
+    | ExpressionStatement Expression
+    | BreakStatement Expression
+    | ContinueStatement Expression
+    deriving Eq
+
+instance Show Statement
+  where
+    show (LetStatement identifier typeName definition) = concat
+        ["let ", show identifier, ": ", show typeName, " := ", show definition]
+    show (CompoundStatement statements) = "begin "
+        <> intercalate "; " (show <$> statements) <> " end"
+    show (CallStatement name parameters) = show name <> "("
+        <> intercalate ", " (show <$> parameters) <> ")"
+    show (ExpressionStatement expression) = show expression
+    show (BreakStatement break') = "break " <> show break'
+    show (ContinueStatement continue') = "continue " <> show continue'
+
+data ConstantDefinition =
+    ConstantDefinition Identifier TypeName Literal
+    deriving Eq
+
+instance Show ConstantDefinition
+  where
+    show (ConstantDefinition identifier typeName definition) = concat
+        [show identifier, ": ", show typeName, " := ", show definition, ";"]
+
+data Parameter = Parameter Identifier TypeName
+    deriving Eq
+
+instance Show Parameter
+  where
+    show (Parameter identifier typeName) =
+        show identifier <> ": " <> show typeName
+
+data ProcedureDeclaration
+    = ProcedureDeclaration Identifier [Parameter]
+    | ProcedureDefinition Identifier [Parameter] Bool [ConstantDefinition] Statement
+    deriving Eq
+
+instance Show ProcedureDeclaration
+  where
+    show (ProcedureDeclaration procedureName parameters) =
+        "proc " <> show procedureName <> showParameters parameters <> "; extern;"
+    show (ProcedureDefinition procedureName parameters exports constants body)
+        = "proc " <> show procedureName <> showParameters parameters <> ";"
+        <> showAttributes exports
+        <> showConstants constants
+        <> show body <> ";"
+
+data VariableDeclaration
+    = VariableDeclaration Identifier TypeName
+    | VariableDefinition Identifier TypeName (Maybe Literal) Bool
+    deriving Eq
+
+instance Show VariableDeclaration
+  where
+    show (VariableDeclaration identifier typeName)
+        = show identifier <> ": " <> show typeName <> "; extern;"
+    show (VariableDefinition identifier typeName initialValue exports)
+        = show identifier <> ": " <> show typeName
+        <> maybe "" ((" = " <>) . show) initialValue <> ";"
+        <> showAttributes exports
+
+data Program = Program [ConstantDefinition] [VariableDeclaration] [ProcedureDeclaration] Statement
+    deriving Eq
+
+instance Show Program
+  where
+    show (Program constants globals procedures body)
+        = showConstants constants <> showVariables globals
+        <> unlines (show <$> procedures) <> show body <> "."
+
+showAttributes :: Bool -> String
+showAttributes True = " export;"
+showAttributes False = ""
+
+showParameters :: [Parameter] -> String
+showParameters parameters =
+    "(" <> intercalate ", " (show <$> parameters) <> ")"
+
+showConstants :: [ConstantDefinition] -> String
+showConstants constants
+    | null constants = ""
+    | otherwise = " const " <> unwords (show <$> constants) <> "\n"
+
+showVariables :: [VariableDeclaration] -> String
+showVariables variables
+    | null variables = ""
+    | otherwise = " var " <> unwords (show <$> variables) <> "\n"
diff --git a/src/Language/Elna/Parser.hs b/src/Language/Elna/Parser.hs
new file mode 100644
index 0000000..bf5b4e5
--- /dev/null
+++ b/src/Language/Elna/Parser.hs
@@ -0,0 +1,37 @@
+module Language.Elna.Parser
+    ( Parser
+    , programP
+    ) where
+
+import Control.Monad (void)
+import Data.Text (Text)
+import Data.Void (Void)
+import Language.Elna.AST
+    ( Statement(..)
+    , Program(..)
+    )
+import Text.Megaparsec (Parsec)
+import Text.Megaparsec.Char (space1)
+import qualified Text.Megaparsec.Char.Lexer as Lexer
+
+type Parser = Parsec Void Text
+
+space :: Parser ()
+space = Lexer.space space1 (Lexer.skipLineComment "//")
+    $ Lexer.skipBlockComment "{" "}"
+
+lexeme :: forall a. Parser a -> Parser a
+lexeme = Lexer.lexeme space
+
+symbol :: Text -> Parser Text
+symbol = Lexer.symbol space
+
+beginP :: Parser ()
+beginP = void $ symbol "begin"
+
+endP :: Parser ()
+endP = void $ symbol  "end"
+
+programP :: Parser Program
+programP = beginP >> endP >> symbol "."
+    >> pure (Program mempty mempty mempty $ CompoundStatement mempty)
diff --git a/src/Main.hs b/src/Main.hs
new file mode 100644
index 0000000..bb8be4c
--- /dev/null
+++ b/src/Main.hs
@@ -0,0 +1,13 @@
+module Main where
+
+import Language.Elna.Parser (programP)
+import Text.Megaparsec (runParser, errorBundlePretty)
+import qualified Data.Text.IO as Text
+
+main :: IO ()
+main = Text.getContents
+    >>= withParseResult . runParser programP ""
+  where
+    withParseResult (Right _) = pure ()
+    withParseResult (Left errorBundle) =
+        putStr $ errorBundlePretty errorBundle