Return to Answer

• You can't use array property declarations/expressions in classes, not even in PHP 7.

  protected $var["x"] = "Nope";
                ⇑
  

• Confusing [ with opening curly braces { or parentheses ( is a common oversight.

  foreach [$a as $b)
          ⇑
  

  Or even:

  function foobar[$a, $b, $c] {
                 ⇑
  

• Or trying to dereference constants (before PHP 5.6) as arrays:

  $var = const[123];
         ⇑
  

  At least PHP interprets that const as a constant name.

  If you meant to access an array variable (which is the typical cause here), then add the leading $ sigil - so it becomes a $varname.

• You can't use array property declarations/expressions in classes, not even in PHP 7.

  protected $var["x"] = "Nope";
                ⇑
  

• Confusing [ with opening curly braces { or parentheses ( is a common oversight.

  foreach [$a as $b)
          ⇑
  

  Or even:

  function foobar[$a, $b, $c] {
                 ⇑
  

• Or trying to dereference constants (before PHP 5.6) as arrays:

  $var = const[123];
         ⇑
  

  At least PHP interprets that const as a constant name.

  If you meant to access an array variable (which is the typical cause here), then add the leading $ sigil - so it becomes a $varname.

• You are trying to use the global keyword on a member of an associative array. This is not valid syntax:

  global $var['key'];
  

These days, the unexpected [ array bracket is commonly seen on outdated PHP versions. The short array syntax is available since PHP >= 5.4. Older installations only support array().

Array function result dereferencing is likewise not avaiable for older PHP versions:

$result = get_whatever()["key"];
                        ⇑

Reference - What does this error mean in PHP? - "Syntax error, unexpected [" shows the most common and practical workarounds.

• PHP syntax for dereferencing function result → possible as of PHP 5.4
• PHP syntax error, unexpected '['
• Shorthand for arrays: is there a literal syntax like {} or []?
• PHP 5.3.10 vs PHP 5.5.3 syntax error unexpected '['
• PHP Difference between array() and []
• PHP Array Syntax Parse Error Left Square Bracket "["

Btw, there are also preprocessors and PHP 5.4 syntax down-converters if you're really clingy with older + slower PHP versions.

• You can't use array property declarations/expressions in classes, not even in PHP7.

  protected $var["x"] = "Nope";
                ⇑
  

• Confusing [ with opening curly braces { or parens ( is a common oversight.

  foreach [$a as $b)
          ⇑
  

  Or even:

  function foobar[$a, $b, $c] {
                 ⇑
  

• Or trying to dereference constants (before PHP 5.6) as arrays:

  $var = const[123];
         ⇑
  

  At least PHP interprets that const as constant name.

  If you meant to access an array variable (which is the typical cause here), then add the leading $ sigil - so it becomes a $varname.

• Again mismatches with ) parentheses or } curly braces are common:

  function foobar($a, $b, $c] {
                            ⇑ 
  

• Or trying to end an array where there isn't one:

  $var = 2];
  

  Which often occurs in multi-line and nested array declarations.

  $array = [1,[2,3],4,[5,6[7,[8],[9,10]],11],12]],15];
                                                ⇑
  

  If so, use your IDE for bracket matching to find any premature ] array closure. At the very least use more spacing and newlines to narrow it down.

These days, the unexpected [ array bracket is commonly seen on outdated PHP versions. The short array syntax is available since PHP >= 5.4. Older installations only support array().

Array function result dereferencing is likewise not available for older PHP versions:

$result = get_whatever()["key"];
                      ⇑

Reference - What does this error mean in PHP? - "Syntax error, unexpected \[" shows the most common and practical workarounds.

• PHP syntax for dereferencing function result → possible as of PHP 5.4
• PHP syntax error, unexpected '['
• Shorthand for arrays: is there a literal syntax like {} or []?
• PHP 5.3.10 vs PHP 5.5.3 syntax error unexpected '['
• PHP Difference between array() and []
• PHP Array Syntax Parse Error Left Square Bracket "["

BTW, there are also preprocessors and PHP 5.4 syntax down-converters if you're really clingy with older + slower PHP versions.

• You can't use array property declarations/expressions in classes, not even in PHP 7.

  protected $var["x"] = "Nope";
                ⇑
  

• Confusing [ with opening curly braces { or parentheses ( is a common oversight.

  foreach [$a as $b)
          ⇑
  

  Or even:

  function foobar[$a, $b, $c] {
                 ⇑
  

• Or trying to dereference constants (before PHP 5.6) as arrays:

  $var = const[123];
         ⇑
  

  At least PHP interprets that const as a constant name.

  If you meant to access an array variable (which is the typical cause here), then add the leading $ sigil - so it becomes a $varname.

• Again mismatches with ) parentheses or } curly braces are common:

  function foobar($a, $b, $c] {
                            ⇑
  

• Or trying to end an array where there isn't one:

  $var = 2];
  

  Which often occurs in multi-line and nested array declarations.

  $array = [1,[2,3],4,[5,6[7,[8],[9,10]],11],12]],15];
                                               ⇑
  

  If so, use your IDE for bracket matching to find any premature ] array closure. At the very least use more spacing and newlines to narrow it down.

Reference - What does this error mean in PHP? - "Syntax error, unexpected [" shows the most common and practical workarounds.

• PHP syntax for dereferencing function result → possible as of PHP 5.4
• PHP syntax error, unexpected '['
• Shorthand for arrays: is there a literal syntax like {} or []?
• PHP 5.3.10 vs PHP 5.5.3 syntax error unexpected '['
• PHP Difference between array() and []
• PHP Array Syntax Parse Error Left Square Bracket "["

• You can't use array property declarations/expressions in classes, not even in PHP7.

  protected $var["x"] = "Nope";
                ⇑
  

• Confusing [ with opening curly braces { or parens ( is a common oversight.

  foreach [$a as $b)
          ⇑
  

  Or even:

  function foobar[$a, $b, $c] {
                 ⇑
  

• Or trying to dereference constants (before PHP 5.6) as arrays:

  $var = const[123];
         ⇑
  

  At least PHP interprets that const as constant name.

  If you meant to access an array variable (which is the typical cause here), then add the leading $ sigil - so it becomes a $varname.

Reference - What does this error mean in PHP? - "Syntax error, unexpected [" shows the most common and practical workarounds.

• PHP syntax for dereferencing function result → possible as of PHP 5.4
• PHP syntax error, unexpected '['
• Shorthand for arrays: is there a literal syntax like {} or []?
• PHP 5.3.10 vs PHP 5.5.3 syntax error unexpected '['
• PHP Difference between array() and []
• PHP Array Syntax Parse Error Left Square Bracket "["

• You can't use array property declarations/expressions in classes, not even in PHP7.

  protected $var["x"] = "Nope";
                ⇑
  

• Confusing [ with opening curly braces { or parens ( is a common oversight.

  foreach [$a as $b)
          ⇑
  

  Or even:

  function foobar[$a, $b, $c] {
                 ⇑
  

• Or trying to dereference constants (before PHP 5.6) as arrays:

  $var = const[123];
         ⇑
  

  At least PHP interprets that const as constant name.

  If you meant to access an array variable (which is the typical cause here), then add the leading $ sigil - so it becomes a $varname.