Compiler/Verifying syntax: Difference between revisions

=={{header|ALGOL W}}==

Includes the test cases from the Go sample. Note, strings are limited to 256 characters in Algol W.

% verify expressions match expected syntax %

procedure stmt ( string(256) value text ) ; begin

stmt( "j & k" );

stmt( "l or _m" )

{{out}}

<pre>

 

=={{header|C}}==

// http://www.rosettacode.org/wiki/Compiler/_Verifying_Syntax

 

{

for( int i = 0; i < sizeof(tests)/sizeof(*tests); i++ ) parse(tests[i]);

{{out}}

<pre>

 

In particular, after substitutions, "= not", "+ not" etc. would be allowed by the Go parser so we need to exclude them. Curiously, the Go parser allows something like "2 < 3 < 4" even though it doesn't compile. We need therefore to exclude that also (see Talk page).

 

import (

fmt.Println()

}

 

{{out}}

"false" -> identifier cannot begin with an underscore

</pre>

 

=={{header|Julia}}==

((i = findlast('(', s)) == nothing) && return (s, false)

((j = findfirst(')', s[i:end])) == nothing) && return (s, false)

println("The compiler parses the statement { $s } and outputs: ", okparse(s))

end

<pre>

The compiler parses the statement { not 3 < 4 or (true or 3 / 4 + 8 * 5 - 5 * 2 < 56) and 4 * 3 < 12 or not true } and outputs: true

The compiler parses the statement { 2 < 5 < 9 } and outputs: false

</pre>

 

=={{header|Perl}}==

Added 'not' and non-assoc fixes.

Cooler output.

 

use strict; # http://www.rosettacode.org/wiki/Compiler/_Verifying_Syntax

j & k

l or _m

{{out}}

<pre>

 

=={{header|Phix}}==

{{out}}

Note that "= not c" fails, whereas "= (not c)" passes, see talk page. (Arguably the task definition should be fixed.)

=={{header|Raku}}==

Format of task grammar is changed from EBNF to ABNF to cater for the Grammar::ABNF module and testing data is taken from the Perl entry.

 

use Grammar::ABNF;

DATA

 

{{out}}

<pre>False 3 + not 5

False l or _m

True UPPER_cAsE_aNd_letter_and_12345_test

</pre>