File: is_silent_command.js

package info (click to toggle)
node-stdlib 0.0.96%2Bds1%2B~cs0.0.429-2
  • links: PTS, VCS
  • area: main
  • in suites: sid, trixie
  • size: 421,476 kB
  • sloc: javascript: 1,562,831; ansic: 109,702; lisp: 49,823; cpp: 27,224; python: 7,871; sh: 6,807; makefile: 6,089; fortran: 3,102; awk: 387
file content (84 lines) | stat: -rw-r--r-- 1,881 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
/**
* @license Apache-2.0
*
* Copyright (c) 2019 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*    http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

'use strict';

// VARIABLES //

var RE_NON_WHITESPACE = /\S/;
var SEMICOLON = 59; // character code


// MAIN //

/**
* Asserts whether a command is "silent" (i.e., terminates in a semicolon).
*
* @private
* @param {string} code - unevaluated command
* @returns {boolean} boolean indicating whether a command is "silent"
*
* @example
* var bool = isSilentCommand( '' );
* // returns false
*
* @example
* var bool = isSilentCommand( ';' );
* // returns true
*
* @example
* var bool = isSilentCommand( 'var x = 3' );
* // returns false
*
* @example
* var bool = isSilentCommand( 'var x = 3;' );
* // returns true
*
* @example
* var bool = isSilentCommand( 'var x = 3; var y = 4' );
* // returns false
*
* @example
* var bool = isSilentCommand( 'var x = 3; var y = 4;' );
* // returns true
*
* @example
* var bool = isSilentCommand( 'var x = 3;\nvar y = 4   ' );
* // returns false
*
* @example
* var bool = isSilentCommand( 'var x = 3;\nvar y = 4;\n' );
* // returns true
*/
function isSilentCommand( code ) {
	var i;
	for ( i = code.length-1; i >= 0; i-- ) {
		if ( code.charCodeAt( i ) === SEMICOLON ) {
			return true;
		}
		if ( RE_NON_WHITESPACE.test( code[ i ] ) ) {
			return false;
		}
	}
	return false;
}


// EXPORTS //

module.exports = isSilentCommand;