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microlang.php
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microlang.php
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<?php
//
// FreeBSD 2-clause license
//
// microlang.php
//
// A php microlang interpreter
//
// microlang version 1.3
// php interpreter version 1.3.5
//
// Copyright (c) 2022, Paolo Bertani - Kalei S.r.l.
//
// All rights reserved.
//
// 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 THE COPYRIGHT OWNER OR CONTRIBUTORS 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.
//
function microlang( $code, &$vars, $options = null )
{
// Begin
$keywords = [
'goto',
'gosub',
'return',
'exit',
'=',
'substring',
'position',
'between',
'replace',
'trim',
'len',
'int',
'float',
'string',
'typeof',
'+',
'-',
'*',
'/',
'%',
'if', 'then', 'else', '==', '!=', '>', '<', '>=', '<=',
',',
'(',
')'
];
if( ! isset( $options ) )
{
$options = [];
}
$max_iterations = isset( $options[ 'max_iterations' ] ) ? $options[ 'max_iterations' ] : 1000;
if( ! is_int( $max_iterations ) ) return "`max_iterations` options must be int";
$max_str_len = isset( $options[ 'max_str_len' ] ) ? $options[ 'max_str_len' ] : 1048576;
if( ! is_int( $max_str_len ) ) return "`max_strlen` options must be int";
if( isset( $options[ 'action' ] ) )
{
if( $options[ 'action' ] === 'execute' ) $execute = true;
else if( $options[ 'action' ] === 'analyze' ) $execute = false;
else return "`action` option must be either `execute` or `analyze`";
}
else
{
$execute = true;
}
$labels = [];
$stack = [];
if( ! isset( $vars ) )
{
$vars = [];
}
if( ! is_array( $vars ) )
{
return "input data provided is not array";
}
// check and store input types
$typs = [];
foreach( $vars as $key => $value )
{
if( is_int( $value ) ) $typs[ $key ] = 'int';
elseif( is_string( $value ) ) $typs[ $key ] = 'string';
elseif( is_float( $value ) ) $typs[ $key ] = 'float';
else return "unsupported variable type: $key";
}
// convert windows linefeeds to unix linefeeds if any
$code = str_replace( "\r\n", "\n", $code );
// explode code
$lines = explode( "\n", $code );
// remove comments
$n = count( $lines );
for( $i = 0; $i < $n; $i++ )
{
$l = $lines[ $i ];
$idx = mb_strpos( $l, '//' );
if( $idx !== false )
{
$l = mb_substr8( $l, 0, $idx );
}
$l = trim( $l );
$lines[ $i ] = $l;
}
// tokenize
$newlines = $lines;
$lines = [];
$y = -1;
$y1b = $y + 1;
$m = count( $newlines );
for( $k = 0; $k < $m; $k++ )
{
$l = $newlines[ $k ];
$y++;
$y1b = $y + 1;
$parts = microlang_splitline( $l, $error );
if( $error !== '' ) return "$error$y1b";
$tokens = [];
$n = count( $parts );
for( $i = 0; $i < $n; $i++ )
{
$p = $parts[ $i ];
// Keywords
if( in_array( $p, $keywords ) )
{
$tokens[] = [ 'type' => 'keyword', 'symbol' => $p, 'value' => null, 'vtype' => null ];
if( $i < $n - 1 && $parts[ $i + 1 ] === '=' ) return "keywords cannot be used for variable names ( $p ): $y1b";
continue;
}
// Labels
if( substr8( $p, -1, 1 ) === ":" && $i === 0 )
{
$p = mb_substr8( $p, 0, -1 );
if( in_array( $p, $keywords ) ) return "keywords cannot be used for label names ( $p ): $y1b";
$tokens[] = [ 'type' => 'label', 'symbol' => $p, 'value' => $y, 'vtype' => null ];
if( isset( $labels[ $p ] ) ) return "Label $p duplicate: $y1b";
$labels[ $p ] = $y;
continue;
}
if( substr8( $p, -1, 1 ) === ":" && $i > 0 )
{
return "unexpected label: $y1b";
}
// Strings
if( $p === '""' )
{
$tokens[] = [ 'type' => 'value', 'symbol' => null, 'value' => "", 'vtype' => 'string' ];
continue;
}
if( substr8( $p, 0, 1 ) === '"' )
{
if( substr8( $p, -1, 1 ) === '"' && mb_strlen( $p ) > 1 )
{
$tokens[] = [ 'type' => 'value', 'symbol' => null, 'value' => substr8( $p, 1, -1 ), 'vtype' => 'string' ];
continue;
}
$value = substr8( $p, 1, -1 );
if( substr8( $p, -1, 1 ) !== '"' ) return "string not closed: $y1b";
$tokens[] = [ 'type' => 'value', 'symbol' => null, 'value' => $value, 'vtype' => 'string' ];
continue;
}
// Integers
if( preg_match( '/^-?\d+(e?\d+|E?\d+|(e-)?\d+|(E-)?\d+)?$/', $p ) === 1 )
{
if( floatval( $p ) > PHP_INT_MAX || floatval( $p ) < PHP_INT_MIN ) return "overflow: $y1b";
$tokens[] = [ 'type' => 'value', 'symbol' => null, 'value' => intval( $p ), 'vtype' => 'int' ];
continue;
}
// Floats
if( preg_match( '/^-?\d*\.\d+(e?\d+|E?\d+|(e-)?\d+|(E-)?\d+)?$/', $p ) === 1 )
{
$tokens[] = [ 'type' => 'value', 'symbol' => null, 'value' => floatval( $p ), 'vtype' => 'float' ];
continue;
}
// Variable names
$tokens[] = [ 'type' => 'variable', 'symbol' => $p, 'value' => null, 'vtype' => null ];
}
$lines[] = $tokens;
}
// execute
$y = 0;
$lines_count = count( $lines );
$iter = 0;
$vars[ 'cast_failed' ] = 0;
while( true )
{
$done = false;
$y1b = $y + 1;
if( $iter > $max_iterations && $max_iterations !== 0 ) return "max iterations exceeded: $y1b";
$tok = $lines[ $y ];
$tn = count( $tok );
if( $tn === 0 ) $done = true;
if( $tn === 1 && $tok[ 0 ][ 'type' ] === 'label' ) $done = true;
$tokens = [];
for( $i = 0; $i < $tn; $i++ )
{
$t = $tok[ $i ];
if( $t[ 'type' ] === 'label' || $t[ 'type' ] === 'value' || $t[ 'type' ] === 'keyword' )
{
$tokens[] = $t;
}
elseif( $t[ 'type' ] === 'variable' )
{
if( isset( $typs[ $t[ 'symbol' ] ] ) )
{
$t[ 'value' ] = $vars[ $t[ 'symbol' ] ];
$t[ 'vtype' ] = $typs[ $t[ 'symbol' ] ];
$tokens[] = $t;
}
elseif( isset( $labels[ $t[ 'symbol' ] ] ) )
{
$t[ 'type' ] = 'label';
$t[ 'value' ] = $labels[ $t[ 'symbol' ] ];
$tokens[] = $t;
}
else
{
$t[ 'value' ] = null;
$t[ 'vtype' ] = null;
$tokens[] = $t;
}
}
}
$t0s = $done ? '' : $tokens[ 0 ][ 'symbol' ];
$tcn = $done ? 0 : count( $tokens );
// Goto
if( ! $done && microlang_parse( $tokens, [ 'goto', ':' ] ) )
{
$done = true;
$label = $tokens[ 1 ][ 'symbol' ];
if( isset( $labels[ $label ] ) )
{
$iter++;
if( $execute )
{
$y = $labels[ $label ];
continue;
}
}
else return "unknown label `$label`: $y1b";
}
// Gosub
if( ! $done && microlang_parse( $tokens, [ 'gosub', ':' ] ) )
{
$done = true;
$label = $tokens[ 1 ][ 'symbol' ];
if( isset( $labels[ $label ] ) )
{
$iter++;
if( $execute )
{
$stack[] = $y;
$y = $labels[ $label ];
continue;
}
}
else return "unknown label `$label`: $y1b";
}
// Return
if( ! $done && microlang_parse( $tokens, [ 'return' ] ) )
{
$done = true;
if( $execute )
{
if( count( $stack ) === 0 ) return "return without gosub: $y1b";
$y = array_pop( $stack );
continue;
}
}
// Exit
if( ! $done && microlang_parse( $tokens, [ 'exit' ] ) )
{
$done = true;
if( $execute )
{
break;
}
}
// Exit with error message
if( ! $done && microlang_parse( $tokens, [ 'exit', '#' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "*" ); if( $err !== '' ) return $err . $y1b;
return $tokens[ 1 ][ 'value' ] . '';
}
// Int, Float, String declaration with first assignment
if( ! $done && ( microlang_parse( $tokens, [ 'int', '@', '=', '#' ] ) || microlang_parse( $tokens, [ 'float', '@', '=', '#' ] ) || microlang_parse( $tokens, [ 'string', '@', '=', '#' ] ) ) )
{
$err = microlang_typecheck( $execute, $tokens, "U" . strtoupper( $tokens[0]['symbol'][0] ) ); if( $err !== '' ) return $err . $y1b;
$typs[ $tokens[ 1 ][ 'symbol' ] ] = $tokens[ 0 ][ 'symbol' ];
$vars[ $tokens[ 1 ][ 'symbol' ] ] = $tokens[ 3 ][ 'value' ];
$done = true;
}
// Int, Float, String declaration
if( ! $done && ( $t0s === 'int' || $t0s === 'float' || $t0s === 'string' ) && $tcn >= 2 )
{
$j = 1;
while( true )
{
if( $tokens[ $j ][ 'type' ] === 'variable' )
{
if( isset( $typs[ $tokens[ $j ][ 'symbol' ] ] ) )
{
return "variable `{$tokens[ $j ][ 'symbol' ]}` already defined: $y1b";
}
$typs[ $tokens[ $j ][ 'symbol' ] ] = $t0s;
$vars[ $tokens[ $j ][ 'symbol' ] ] = null;
}
else
{
return "variable expected: $y1b";
}
if( $j >= $tcn - 1 ) break;
if( $j < $tcn - 2 )
{
$j++;
if( $tokens[ $j ][ 'symbol' ] !== ',' ) return "`,` expected: $y1b";
$j++;
}
}
$done = true;
}
// = Assignment
if( ! $done && microlang_parse( $tokens, [ '@', '=', '#' ] ) )
{
if( $t0s === 'cast_failed' ) return "`cast_failed` is a reserved variable name: $y1b";
$err = microlang_typecheck( $execute, $tokens, "+1" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ];
}
$done = true;
}
if( ! $done && microlang_parse( $tokens, [ 'K', '=', '#' ] ) )
{
return "keywords cannot be used for variable names ( {$tokens[ 0 ][ 'symbol' ]} ): $y1b";
}
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'K' ] ) )
{
return "keyword unexpected at right side of assignment ( {$tokens[ 2 ][ 'symbol' ]} ): $y1b";
}
// Substring
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'substring', '(', '#', ',', '#', ',', '#', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "sSII" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
$vars[ $t0s ] = mb_substr8( $tokens[ 4 ][ 'value' ], $tokens[ 6 ][ 'value' ], $tokens[ 8 ][ 'value' ] );
}
$done = true;
}
// Position
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'position', '(', '#', ',', '#', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "iSS" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
if( $tokens[ 4 ][ 'value' ] === '' || $tokens[ 6 ][ 'value' ] === '' )
{
$vars[ $t0s ] = -1;
}
else
{
$vars[ $t0s ] = mb_strpos( $tokens[ 4 ][ 'value' ], $tokens[ 6 ][ 'value' ] );
if( $vars[ $t0s ] === false ) $vars[ $t0s ] = -1;
}
}
$done = true;
}
// Replace
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'replace', '(', '#', ',', '#', ',', '#', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "sSSS" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
$vars[ $t0s ] = str_replace( $tokens[ 6 ][ 'value' ], $tokens[ 8 ][ 'value' ], $tokens[ 4 ][ 'value' ] );
if( mb_strlen( $vars[ $t0s ] ) > $max_str_len ) return "string too long: $y1b";
}
$done = true;
}
// Between
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'between', '(', '#', ',', '#', ',', '#', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "sSSS" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
$vars[ $t0s ] = microlang_between( $tokens[ 4 ][ 'value' ], $tokens[ 6 ][ 'value' ], $tokens[ 8 ][ 'value' ] );
if( $vars[ $t0s ] === false ) $vars[ $t0s ] = "";
}
$done = true;
}
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'between', '(', '#', ',', '#', ',', '#', ',', '@', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "sSSSi" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
$vars[ $t0s ] = microlang_between( $tokens[ 4 ][ 'value' ], $tokens[ 6 ][ 'value' ], $tokens[ 8 ][ 'value' ] );
if( $vars[ $t0s ] === false )
{
$vars[ $t0s ] = "";
$vars[ $tokens[ 10 ][ 'symbol' ] ] = 0;
}
else
{
$vars[ $tokens[ 10 ][ 'symbol' ] ] = 1;
}
}
$done = true;
}
// Trim
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'trim', '(', '#', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "sS" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
$vars[ $t0s ] = trim( $tokens[ 4 ][ 'value' ], " \n\r\t" );
}
$done = true;
}
// Len
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'len', '(', '#', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "iS" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
$vars[ $t0s ] = mb_strlen( $tokens[ 4 ][ 'value' ] );
}
$done = true;
}
// Typeof
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'typeof', '(', '#', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "s+" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
$vars[ $t0s ] = $tokens[ 4 ][ 'vtype' ];
}
$done = true;
}
// Int
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'int', '(', '#', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "i*" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
if( $tokens[ 4 ][ 'vtype' ] === 'string' && preg_match( '/^-?\d+(e?\d+|E?\d+|(e-)?\d+|(E-)?\d+)?$/', $tokens[ 4 ][ 'value' ] ) === 0 && preg_match( '/^-?\d*\.\d+(e?\d+|E?\d+|(e-)?\d+|(E-)?\d+)?$/', $tokens[ 4 ][ 'value' ] ) === 0 )
{
$vars[ $t0s ] = ( int )0;
$vars[ 'cast_failed' ] = 1;
}
else
{
if( floatval( $tokens[ 4 ][ 'value' ] ) > PHP_INT_MAX || floatval( $tokens[ 4 ][ 'value' ] ) < PHP_INT_MIN )
{
$vars[ $t0s ] = ( int )0;
$vars[ 'cast_failed' ] = 1;
}
else
{
$vars[ $t0s ] = intval( $tokens[ 4 ][ 'value' ] );
$vars[ 'cast_failed' ] = 0;
}
}
}
$done = true;
}
// Float
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'float', '(', '#', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "n*" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
if( $tokens[ 4 ][ 'vtype' ] === 'string' && preg_match( '/^-?\d+(e?\d+|E?\d+|(e-)?\d+|(E-)?\d+)?$/', $tokens[ 4 ][ 'value' ] ) === 0 && preg_match( '/^-?\d*\.\d+(e?\d+|E?\d+|(e-)?\d+|(E-)?\d+)?$/', $tokens[ 4 ][ 'value' ] ) === 0 )
{
$vars[ $t0s ] = ( float )0;
$vars[ 'cast_failed' ] = 1;
$typs[ $t0s ] = 'float';
}
else
{
$vars[ $t0s ] = floatval( $tokens[ 4 ][ 'value' ] );
$vars[ 'cast_failed' ] = 0;
$typs[ $t0s ] = 'float';
}
}
$done = true;
}
// String
if( ! $done && microlang_parse( $tokens, [ '@', '=', 'string', '(', '#', ')' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "s*" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
$vars[ $t0s ] = '' . $tokens[ 4 ][ 'value' ];
}
$done = true;
}
// + Sum
if( ! $done && microlang_parse( $tokens, [ '@', '=', '#', '+', '#' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "+12" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
if( $tokens[ 2 ][ 'vtype' ] === 'string' )
{
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ] . $tokens[ 4 ][ 'value' ];
if( mb_strlen( $vars[ $t0s ] ) > $max_str_len ) return "string too long: $y1b";
}
elseif( $tokens[ 2 ][ 'vtype' ] === 'int' )
{
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ] + $tokens[ 4 ][ 'value' ];
if( $vars[ $t0s ] > PHP_INT_MAX || $vars[ $t0s ] < PHP_INT_MIN ) return "overflow: $y1b";
}
elseif( $tokens[ 2 ][ 'vtype' ] === 'float' )
{
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ] + $tokens[ 4 ][ 'value' ];
}
}
$done = true;
}
// - Diff
if( ! $done && microlang_parse( $tokens, [ '@', '=', '#', '-', '#' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "n12" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
if( $tokens[ 2 ][ 'vtype' ] === 'int' )
{
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ] - $tokens[ 4 ][ 'value' ];
if( $vars[ $t0s ] > PHP_INT_MAX || $vars[ $t0s ] < PHP_INT_MIN ) return "overflow: $y1b";
}
elseif( $tokens[ 2 ][ 'vtype' ] === 'float' )
{
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ] - $tokens[ 4 ][ 'value' ];
}
}
$done = true;
}
// * Mult
if( ! $done && microlang_parse( $tokens, [ '@', '=', '#', '*', '#' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "n12" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
if( $tokens[ 2 ][ 'vtype' ] === 'int' )
{
$rt = 'int';
if( isset( $typs[ $t0s ] ) && $typs[ $t0s ] !== $rt ) return "variable `$t0s` must be $rt: $y1b";
$typs[ $t0s ] = $rt;
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ] * $tokens[ 4 ][ 'value' ];
if( $vars[ $t0s ] > PHP_INT_MAX || $vars[ $t0s ] < PHP_INT_MIN ) return "overflow: $y1b";
}
elseif( $tokens[ 2 ][ 'vtype' ] === 'float' )
{
$rt = 'float';
if( isset( $typs[ $t0s ] ) && $typs[ $t0s ] !== $rt ) return "variable `$t0s` must be $rt: $y1b";
$typs[ $t0s ] = $rt;
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ] * $tokens[ 4 ][ 'value' ];
}
}
$done = true;
}
// / Div
if( ! $done && microlang_parse( $tokens, [ '@', '=', '#', '/', '#' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "n12" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
if( $tokens[ 4 ][ 'value' ] === 0 ) return "division by zero: $y1b";
if( $tokens[ 2 ][ 'vtype' ] === 'int' )
{
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ] / $tokens[ 4 ][ 'value' ];
if( $vars[ $t0s ] > PHP_INT_MAX || $vars[ $t0s ] < PHP_INT_MIN ) return "overflow: $y1b";
$vars[ $t0s ] = intdiv( $tokens[ 2 ][ 'value' ], $tokens[ 4 ][ 'value' ] );
}
elseif( $tokens[ 2 ][ 'vtype' ] === 'float' )
{
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ] / $tokens[ 4 ][ 'value' ];
}
}
$done = true;
}
// % Modulo
if( ! $done && microlang_parse( $tokens, [ '@', '=', '#', '%', '#' ] ) )
{
$err = microlang_typecheck( $execute, $tokens, "iII" ); if( $err !== '' ) return $err . $y1b;
if( $execute )
{
if( $tokens[ 4 ][ 'value' ] === 0 ) return "division by zero: $y1b";
$vars[ $t0s ] = $tokens[ 2 ][ 'value' ] % $tokens[ 4 ][ 'value' ];
}
$done = true;
}
// If Then [ Else ]
if( ! $done && ( microlang_parse( $tokens, [ 'if', '#', '~', '#', 'then', ':' ] ) || microlang_parse( $tokens, [ 'if', '#', '~', '#', 'then', ':', 'else', ':' ] ) ) )
{
$err = microlang_typecheck( $execute, $tokens, "*1" ); if( $err !== '' ) return $err . $y1b;
if( $tokens[ 5 ][ 'value' ] === null ) return "undefined label `" . $tokens[ 5 ][ 'symbol' ] ."`: $y5b";
if( $tn === 8 && $tokens[ 7 ][ 'value' ] === null ) return "undefined label `" . $tokens[ 7 ][ 'symbol' ] . "`: $y5b";
if( $execute )
{
if( $tokens[ 2 ][ 'symbol' ] === '==' )
{
if( $tokens[ 1 ][ 'value' ] == $tokens[ 3 ][ 'value' ] )
{
$y = $tokens[ 5 ][ 'value' ];
$iter++;
continue;
}
else
{
if( $tn === 8 && $tokens[ 7 ][ 'value' ] !== null )
{
$y = $tokens[ 7 ][ 'value' ];
$iter++;
continue;
}
else
{
$done = true;
}
}
}
if( $tokens[ 2 ][ 'symbol' ] === '!=' )
{
if( $tokens[ 1 ][ 'value' ] != $tokens[ 3 ][ 'value' ] )
{
$y = $tokens[ 5 ][ 'value' ];
$iter++;
continue;
}
else
{
if( $tn === 8 && $tokens[ 7 ][ 'value' ] !== null )
{
$y = $tokens[ 7 ][ 'value' ];
$iter++;
continue;
}
else
{
$done = true;
}
}
}
if( $tokens[ 2 ][ 'symbol' ] === '>' )
{
if( $tokens[ 1 ][ 'value' ] > $tokens[ 3 ][ 'value' ] )
{
$y = $tokens[ 5 ][ 'value' ];
$iter++;
continue;
}
else
{
if( $tn === 8 && $tokens[ 7 ][ 'value' ] !== null )
{
$y = $tokens[ 7 ][ 'value' ];
$iter++;
continue;
}
else
{
$done = true;
}
}
}
if( $tokens[ 2 ][ 'symbol' ] === '<' )
{
if( $tokens[ 1 ][ 'value' ] < $tokens[ 3 ][ 'value' ] )
{
$y = $tokens[ 5 ][ 'value' ];
$iter++;
continue;
}
else
{
if( $tn === 8 && $tokens[ 7 ][ 'value' ] !== null )
{
$y = $tokens[ 7 ][ 'value' ];
$iter++;
continue;
}
else
{
$done = true;
}
}
}
if( $tokens[ 2 ][ 'symbol' ] === '<=' )
{
if( $tokens[ 1 ][ 'value' ] <= $tokens[ 3 ][ 'value' ] )
{
$y = $tokens[ 5 ][ 'value' ];
$iter++;
continue;
}
else
{
if( $tn === 8 && $tokens[ 7 ][ 'value' ] !== null )
{
$y = $tokens[ 7 ][ 'value' ];
$iter++;
continue;
}
else
{
$done = true;
}
}
}
if( $tokens[ 2 ][ 'symbol' ] === '>=' )
{
if( $tokens[ 1 ][ 'value' ] >= $tokens[ 3 ][ 'value' ] )
{
$y = $tokens[ 5 ][ 'value' ];
$iter++;
continue;
}
else
{
if( $tn === 8 && $tokens[ 7 ][ 'value' ] !== null )
{
$y = $tokens[ 7 ][ 'value' ];
$iter++;
continue;
}
else
{
$done = true;
}
}
}
}
else
{
$done = true;
}
}
if( ! $done )
{
return "syntax error: $y1b";
}
$y++;
if( $y >= $lines_count )
{
break;
}
}
unset( $vars[ 'cast_failed' ] );
return "";
}
function microlang_totext( $t )
{
if( $t[ 'symbol' ] !== null )
{
return "`" . $t[ 'symbol' ] + "`";
}
if( $t[ 'vtype' ] === 'string' )
{
return "`\"" . $t[ 'value' ] + "\"`";
}
else if( $t[ 'vtype' ] === 'int' )
{