``javascript
var assert = require('assert')
var valid = require('spdx-expression-validate')
`

Simple License Expressions


`javascript
assert(!valid('Invalid-Identifier'))
assert(valid('GPL-2.0'))
assert(valid('GPL-2.0+'))
assert(valid('LicenseRef-23'))
assert(valid('LicenseRef-MIT-Style-1'))
assert(valid('DocumentRef-spdx-tool-1.2:LicenseRef-MIT-Style-2'))
`

Composite License Expressions

Disjunctive OR Operator


`javascript
assert(valid('(LGPL-2.1 OR MIT)'))
assert(valid('(LGPL-2.1 OR MIT OR BSD-3-Clause)'))
`

Conjunctive AND Operator


`javascript
assert(valid('(LGPL-2.1 AND MIT)'))
assert(valid('(LGPL-2.1 AND MIT AND BSD-2-Clause)'))
`

Exception WITH Operator


`javascript
assert(valid('(GPL-2.0+ WITH Bison-exception-2.2)'))
`

Strict Whitespace Rules

`javascript
assert(!valid('MIT '))
assert(!valid(' MIT'))
assert(!valid('MIT AND BSD-3-Clause'))
``

---

The Software Package Data Exchange (SPDX) specification is the work of the Linux Foundation and its contributors, and is licensed under the terms of the Creative Commons Attribution License 3.0 Unported (SPDX: "CC-BY-3.0"). "SPDX" is a United States federally registered trademark of the Linux Foundation.