Merge remote-tracking branch 'origin/develop' into HEAD

docs/contracts/constant-state-variables.rst

@@ -1,5 +1,7 @@
 .. index:: ! constant
 
+.. _constants:
+
 **************************************
 Constant and Immutable State Variables
 **************************************
@@ -9,6 +11,8 @@ In both cases, the variables cannot be modified after the contract has been cons
 For ``constant`` variables, the value has to be fixed at compile-time, while
 for ``immutable``, it can still be assigned at construction time.
 
+It is also possible to define ``constant`` variables at the file level.
+
 The compiler does not reserve a storage slot for these variables, and every occurrence is
 replaced by the respective value.
 
@@ -26,10 +30,11 @@ Not all types for constants and immutables are implemented at this time. The onl
 ::
 
     // SPDX-License-Identifier: GPL-3.0
-    pragma solidity >=0.7.0 <0.9.0;
+    pragma solidity >0.7.2 <0.9.0;
+
+    uint constant X = 32**22 + 8;
 
     contract C {
-        uint constant X = 32**22 + 8;
         string constant TEXT = "abc";
         bytes32 constant MY_HASH = keccak256("abc");
         uint immutable decimals;

docs/grammar/Solidity.g4

@@ -7,7 +7,7 @@ options { tokenVocab=SolidityLexer; }
 
 /**
  * On top level, Solidity allows pragmas, import directives, and
- * definitions of contracts, interfaces, libraries, structs and enums.
+ * definitions of contracts, interfaces, libraries, structs, enums and constants.
  */
 sourceUnit: (
 	pragmaDirective
@@ -16,6 +16,7 @@ sourceUnit: (
 	| interfaceDefinition
 	| libraryDefinition
 	| functionDefinition
+	| constantVariableDeclaration
 	| structDefinition
 	| enumDefinition
 )* EOF;
@@ -240,6 +241,17 @@ locals [boolean constantnessSet = false, boolean visibilitySet = false, boolean
 	(Assign initialValue=expression)?
 	Semicolon;
 
+/**
+ * The declaration of a constant variable.
+ */
+constantVariableDeclaration
+:
+	type=typeName
+	Constant
+	name=identifier
+	Assign initialValue=expression
+	Semicolon;
+
 /**
  * Parameter of an event.
  */

docs/layout-of-source-files.rst

@@ -5,7 +5,8 @@ Layout of a Solidity Source File
 Source files can contain an arbitrary number of
 :ref:`contract definitions<contract_structure>`, import_ directives,
 :ref:`pragma directives<pragma>` and
-:ref:`struct<structs>`, :ref:`enum<enums>` and :ref:`function<functions>` definitions.
+:ref:`struct<structs>`, :ref:`enum<enums>`, :ref:`function<functions>`
+and :ref:`constant variable<constants>` definitions.
 
 .. index:: ! license, spdx