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Andrej-in-uafabpot
Andrej-in-ua
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[ExpressionLanguage] Added expression language syntax validator
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‎CHANGELOG.md

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@@ -1,6 +1,12 @@
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CHANGELOG
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=========
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5.1.0
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-----
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* added `lint` method to `ExpressionLanguage` class
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* added `lint` method to `Parser` class
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4.0.0
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-----
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‎ExpressionLanguage.php

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@@ -97,6 +97,23 @@ public function parse($expression, array $names)
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return $parsedExpression;
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}
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/**
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* Validates the syntax of an expression.
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*
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* @param Expression|string $expression The expression to validate
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* @param array|null $names The list of acceptable variable names in the expression, or null to accept any names
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*
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* @throws SyntaxError When the passed expression is invalid
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*/
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public function lint($expression, ?array $names): void
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{
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if ($expression instanceof ParsedExpression) {
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return;
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}
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$this->getParser()->lint($this->getLexer()->tokenize((string) $expression), $names);
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}
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/**
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* Registers a function.
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*

‎Parser.php

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@@ -31,6 +31,7 @@ class Parser
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private $binaryOperators;
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private $functions;
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private $names;
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private $lint;
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public function __construct(array $functions)
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{
@@ -90,6 +91,30 @@ public function __construct(array $functions)
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* @throws SyntaxError
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*/
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public function parse(TokenStream $stream, array $names = [])
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{
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$this->lint = false;
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return $this->doParse($stream, $names);
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}
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/**
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* Validates the syntax of an expression.
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*
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* The syntax of the passed expression will be checked, but not parsed.
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* If you want to skip checking dynamic variable names, pass `null` instead of the array.
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*
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* @throws SyntaxError When the passed expression is invalid
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*/
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public function lint(TokenStream $stream, ?array $names = []): void
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{
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$this->lint = true;
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$this->doParse($stream, $names);
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}
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/**
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* @throws SyntaxError
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*/
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private function doParse(TokenStream $stream, ?array $names = []): Node\Node
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{
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$this->stream = $stream;
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$this->names = $names;
@@ -197,13 +222,17 @@ public function parsePrimaryExpression()
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$node = new Node\FunctionNode($token->value, $this->parseArguments());
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} else {
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if (!\in_array($token->value, $this->names, true)) {
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throw new SyntaxError(sprintf('Variable "%s" is not valid.', $token->value), $token->cursor, $this->stream->getExpression(), $token->value, $this->names);
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}
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// is the name used in the compiled code different
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// from the name used in the expression?
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if (\is_int($name = array_search($token->value, $this->names))) {
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if (!$this->lint || \is_array($this->names)) {
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if (!\in_array($token->value, $this->names, true)) {
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throw new SyntaxError(sprintf('Variable "%s" is not valid.', $token->value), $token->cursor, $this->stream->getExpression(), $token->value, $this->names);
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}
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// is the name used in the compiled code different
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// from the name used in the expression?
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if (\is_int($name = array_search($token->value, $this->names))) {
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$name = $token->value;
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}
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} else {
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$name = $token->value;
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}
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‎Tests/ParserTest.php

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@@ -15,6 +15,7 @@
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use Symfony\Component\ExpressionLanguage\Lexer;
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use Symfony\Component\ExpressionLanguage\Node;
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use Symfony\Component\ExpressionLanguage\Parser;
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use Symfony\Component\ExpressionLanguage\SyntaxError;
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class ParserTest extends TestCase
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{
@@ -234,4 +235,98 @@ public function testNameProposal()
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$parser->parse($lexer->tokenize('foo > bar'), ['foo', 'baz']);
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}
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/**
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* @dataProvider getLintData
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*/
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public function testLint($expression, $names, ?string $exception = null)
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{
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if ($exception) {
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$this->expectException(SyntaxError::class);
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$this->expectExceptionMessage($exception);
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}
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$lexer = new Lexer();
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$parser = new Parser([]);
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$parser->lint($lexer->tokenize($expression), $names);
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// Parser does't return anything when the correct expression is passed
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$this->expectNotToPerformAssertions();
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}
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public function getLintData(): array
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{
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return [
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'valid expression' => [
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'expression' => 'foo["some_key"].callFunction(a ? b)',
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'names' => ['foo', 'a', 'b'],
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],
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'allow expression without names' => [
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'expression' => 'foo.bar',
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'names' => null,
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],
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'disallow expression without names' => [
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'expression' => 'foo.bar',
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'names' => [],
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'exception' => 'Variable "foo" is not valid around position 1 for expression `foo.bar',
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],
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'operator collisions' => [
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'expression' => 'foo.not in [bar]',
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'names' => ['foo', 'bar'],
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],
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'incorrect expression ending' => [
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'expression' => 'foo["a"] foo["b"]',
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'names' => ['foo'],
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'exception' => 'Unexpected token "name" of value "foo" '.
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'around position 10 for expression `foo["a"] foo["b"]`.',
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],
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'incorrect operator' => [
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'expression' => 'foo["some_key"] // 2',
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'names' => ['foo'],
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'exception' => 'Unexpected token "operator" of value "/" '.
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'around position 18 for expression `foo["some_key"] // 2`.',
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],
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'incorrect array' => [
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'expression' => '[value1, value2 value3]',
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'names' => ['value1', 'value2', 'value3'],
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'exception' => 'An array element must be followed by a comma. '.
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'Unexpected token "name" of value "value3" ("punctuation" expected with value ",") '.
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'around position 17 for expression `[value1, value2 value3]`.',
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],
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'incorrect array element' => [
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'expression' => 'foo["some_key")',
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'names' => ['foo'],
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'exception' => 'Unclosed "[" around position 3 for expression `foo["some_key")`.',
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],
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'missed array key' => [
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'expression' => 'foo[]',
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'names' => ['foo'],
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'exception' => 'Unexpected token "punctuation" of value "]" around position 5 for expression `foo[]`.',
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],
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'missed closing bracket in sub expression' => [
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'expression' => 'foo[(bar ? bar : "default"]',
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'names' => ['foo', 'bar'],
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'exception' => 'Unclosed "(" around position 4 for expression `foo[(bar ? bar : "default"]`.',
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],
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'incorrect hash following' => [
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'expression' => '{key: foo key2: bar}',
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'names' => ['foo', 'bar'],
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'exception' => 'A hash value must be followed by a comma. '.
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'Unexpected token "name" of value "key2" ("punctuation" expected with value ",") '.
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'around position 11 for expression `{key: foo key2: bar}`.',
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],
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'incorrect hash assign' => [
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'expression' => '{key => foo}',
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'names' => ['foo'],
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'exception' => 'Unexpected character "=" around position 5 for expression `{key => foo}`.',
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],
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'incorrect array as hash using' => [
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'expression' => '[foo: foo]',
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'names' => ['foo'],
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'exception' => 'An array element must be followed by a comma. '.
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'Unexpected token "punctuation" of value ":" ("punctuation" expected with value ",") '.
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'around position 5 for expression `[foo: foo]`.',
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],
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];
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}
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}

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