esutils
esutils (esutils) is utility box for ECMAScript language tools.
API
ast
ast.isExpression(node)
Returns true
if node
is an Expression
as defined in ECMA262 edition 5.1 section 11.
ast.isStatement(node)
Returns true
if node
is a Statement
as defined in ECMA262 edition 5.1 section 12.
ast.isIterationStatement(node)
Returns true
if node
is an IterationStatement
as defined in ECMA262 edition 5.1 section 12.6.
ast.isSourceElement(node)
Returns true
if node
is a SourceElement
as defined in ECMA262 edition 5.1 section 14.
ast.trailingStatement(node)
Returns Statement?
if node
has trailing Statement
.
if (cond)
consequent;
When taking this IfStatement
, returns consequent;
statement.
ast.isProblematicIfStatement(node)
Returns true
if node
is a problematic IfStatement
. If node
is a problematic IfStatement
, node
cannot be represented as an one-to-one JavaScript code.
{
type: 'IfStatement',
consequent: {
type: 'WithStatement',
body: {
type: 'IfStatement',
consequent: {type: 'EmptyStatement'}
}
},
alternate: {type: 'EmptyStatement'}
}
The above node cannot be represented as a JavaScript code, since the top level else
alternate belongs to an inner IfStatement
.
code
code.isDecimalDigit(code)
Return true
if provided code is decimal digit.
code.isHexDigit(code)
Return true
if provided code is hexadecimal digit.
code.isOctalDigit(code)
Return true
if provided code is octal digit.
code.isWhiteSpace(code)
Return true
if provided code is white space. White space characters are formally defined in ECMA262.
code.isLineTerminator(code)
Return true
if provided code is line terminator. Line terminator characters are formally defined in ECMA262.
code.isIdentifierStart(code)
Return true
if provided code can be the first character of ECMA262 Identifier
. They are formally defined in ECMA262.
code.isIdentifierPart(code)
Return true
if provided code can be the trailing character of ECMA262 Identifier
. They are formally defined in ECMA262.
keyword
keyword.isKeywordES5(id, strict)
Returns true
if provided identifier string is a Keyword or Future Reserved Word in ECMA262 edition 5.1. They are formally defined in ECMA262 sections 7.6.1.1 and 7.6.1.2, respectively. If the strict
flag is truthy, this function additionally checks whether id
is a Keyword
or FutureReservedWord
under strict mode.
keyword.isKeywordES6(id, strict)
Returns true
if provided identifier string is a Keyword
or FutureReservedWord
in ECMA262 edition 6. They are formally defined in ECMA262 sections 11.6.2.1 and 11.6.2.2, respectively. If the strict
flag is truthy, this function additionally checks whether id
is a Keyword
or FutureReservedWord
under strict mode.
keyword.isReservedWordES5(id, strict)
Returns true
if provided identifier string is a ReservedWord
in ECMA262 edition 5.1. They are formally defined in ECMA262 section 7.6.1. If the strict
flag is truthy, this function additionally checks whether id
is a ReservedWord
under strict mode.
keyword.isReservedWordES6(id, strict)
Returns true
if provided identifier string is a ReservedWord
in ECMA262 edition 6. They are formally defined in ECMA262 section 11.6.2. If the strict
flag is truthy, this function additionally checks whether id
is a ReservedWord
under strict mode.
keyword.isRestrictedWord(id)
Returns true
if provided identifier string is one of eval
or arguments
. They are restricted in strict mode code throughout ECMA262 edition 5.1 and in ECMA262 edition 6 section 12.1.1.
keyword.isIdentifierNameES5(id)
Return true
if provided identifier string is an IdentifierName
as specified in ECMA262 edition 5.1 section 7.6.
keyword.isIdentifierNameES6(id)
Return true
if provided identifier string is an IdentifierName
as specified in ECMA262 edition 6 section 11.6.
keyword.isIdentifierES5(id, strict)
Return true
if provided identifier string is an Identifier
as specified in ECMA262 edition 5.1 section 7.6. If the strict
flag is truthy, this function additionally checks whether id
is an Identifier
under strict mode.
keyword.isIdentifierES6(id, strict)
Return true
if provided identifier string is an Identifier
as specified in ECMA262 edition 6 section 12.1. If the strict
flag is truthy, this function additionally checks whether id
is an Identifier
under strict mode.
License
Copyright (C) 2013 Yusuke Suzuki (twitter: @Constellation) and other contributors.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
-
Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
-
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.