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SyntaxError: missing = in const declaration

    SyntaxError: Const must be initalized (Edge)
    SyntaxError: missing = in const declaration (Firefox)
    SyntaxError: Missing initializer in const declaration (Chrome)

In this article

SyntaxError

?

. . JavaScript const . . , ( ).

const

var let , const .

js
const COLUMNS;
// SyntaxError: missing = in const declaration

. .

.

js
const COLUMNS = 80;

const, let, var?

const . let , var . .

js
let columns;

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    77. SyntaxError: raw bracket is not allowed in regular expression with unicode flag
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    79. SyntaxError: reference to undeclared private field or method #x
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    83. SyntaxError: string literal contains an unescaped line break
    84. SyntaxError: super() is only valid in derived class constructors
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    86. SyntaxError: Unexpected '#' used outside of class body
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    99. TypeError: already executing generator
    100. TypeError: BigInt value can't be serialized in JSON
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    109. TypeError: can't set prototype of this object
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    111. TypeError: cannot use 'in' operator to search for 'x' in 'y'
    112. TypeError: class constructors must be invoked with 'new'
    113. TypeError: cyclic object value
    114. TypeError: derived class constructor returned invalid value x
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    117. TypeError: invalid 'instanceof' operand 'x'
    118. TypeError: invalid Array.prototype.sort argument
    119. TypeError: invalid assignment to const "x"
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    128. TypeError: X.prototype.y called on incompatible type
    129. URIError: malformed URI sequence
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    1. JavaScript
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