====== Request for Comments: Improved parser error message ======
  * Version: 1.0
  * Date: 2011-05-16
  * Author: Felipe Pena <felipe@php.net>
  * Status: Implemented in 5.4
  * Discussion: [[http://markmail.org/thread/2vptpqr72xumbfsh|May 16, 2011]]


===== Introduction =====

The purpose of this RFC is to propose a naming of our tokens to have an crypto-less parser error messages. This is simply achieved by using an old Bison feature.

==== BC ====

There is no BC break. The token_*() functions aren't affected by the patch.

<code>
$ sapi/cli/php -r 'var_dump(token_name(318));'
string(6) "T_ECHO"
</code>

==== Examples ====

<code>
$ sapi/cli/php -r 'class abc foo'
Patched:
Parse error: syntax error, unexpected 'foo' (T_STRING), expecting '{' in Command line code on line 1

Current:
Parse error: syntax error, unexpected T_STRING, expecting '{' in Command line code on line 1
</code>

<code>
$ sapi/cli/php -r 'function ""'
Patched:
Parse error: syntax error, unexpected '""' (T_CONSTANT_ENCAPSED_STRING), expecting identifier (T_STRING) or '(' in Command line code on line 1

Current:
Parse error: syntax error, unexpected T_CONSTANT_ENCAPSED_STRING, expecting T_STRING or '(' in Command line code on line 1
</code>

<code>
$ sapi/cli/php -r 'echo ::a;'
Patched:
Parse error: syntax error, unexpected '::' (T_PAAMAYIM_NEKUDOTAYIM) in Command line code on line 1
nexpected '::' in Command line code on line 1

Current:
Parse error: syntax error, unexpected T_PAAMAYIM_NEKUDOTAYIM in Command line code on line 1
</code>

<code>
$ sapi/cli/php -r 'echo <<='
Patched:
Parse error: syntax error, unexpected '<<=' (T_SL_EQUAL) in Command line code on line 1

Current:
Parse error: syntax error, unexpected T_SL_EQUAL in Command line code on line 1
</code>

<code>
$ sapi/cli/php -r 'class '
Patched:
Parse error: syntax error, unexpected end of file, expecting identifier (T_STRING) in Command line code on line 1

Current:
Parse error: syntax error, unexpected $end, expecting T_STRING in Command line code on line 1
</code>
===== Patch =====

  * http://felipe.ath.cx/diff/improved-error-message.diff