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man pages section 7: Standards, Environments, Macros, Character Sets, and Miscellany

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Updated: Thursday, June 13, 2019

semver (7)


semver - The semantic versioner for npm


Please see following description for synopsis


SEMVER(7)                                                            SEMVER(7)

       semver - The semantic versioner for npm

         npm install --save semver

       As a node module:

         const semver = require('semver')

         semver.valid('1.2.3') // '1.2.3'
         semver.valid('a.b.c') // null
         semver.clean('  =v1.2.3   ') // '1.2.3'
         semver.satisfies('1.2.3', '1.x || >=2.5.0 || 5.0.0 - 7.2.3') // true
         semver.gt('1.2.3', '9.8.7') // false
         semver.lt('1.2.3', '9.8.7') // true
         semver.valid(semver.coerce('v2')) // '2.0.0'
         semver.valid(semver.coerce('')) // '42.6.7'

       As a command-line utility:

         $ semver -h

         SemVer 5.3.0

         A JavaScript implementation of the http://semver.org/ specification
         Copyright Isaac Z. Schlueter

         Usage: semver [options] <version> [<version> [...]]
         Prints valid versions sorted by SemVer precedence

         -r --range <range>
                 Print versions that match the specified range.

         -i --increment [<level>]
                 Increment a version by the specified level.  Level can
                 be one of: major, minor, patch, premajor, preminor,
                 prepatch, or prerelease.  Default level is 'patch'.
                 Only one version may be specified.

         --preid <identifier>
                 Identifier to be used to prefix premajor, preminor,
                 prepatch or prerelease version increments.

         -l --loose
                 Interpret versions and ranges loosely

         -c --coerce
                 Coerce a string into SemVer if possible
                 (does not imply --loose)

         Program exits successfully if any valid version satisfies
         all supplied ranges, and prints all satisfying versions.

         If no satisfying versions are found, then exits failure.

         Versions are printed in ascending order, so supplying
         multiple versions to the utility will just sort them.

       A   "version"  is  described  by  the  v2.0.0  specification  found  at

       A leading "=" or "v" character is stripped off and ignored.

       A version range is a set of comparators  which  specify  versions  that
       satisfy the range.

       A  comparator  is  composed  of  an operator and a version.  The set of
       primitive operators is:

       o < Less than

       o <= Less than or equal to

       o > Greater than

       o >= Greater than or equal to

       o = Equal.  If no operator is specified, then equality is  assumed,  so
         this operator is optional, but MAY be included.

       For  example,  the  comparator  >=1.2.7 would match the versions 1.2.7,
       1.2.8, 2.5.3, and 1.3.9, but not the versions 1.2.6 or 1.1.0.

       Comparators can be joined by whitespace to form a comparator set, which
       is satisfied by the intersection of all of the comparators it includes.

       A  range  is  composed of one or more comparator sets, joined by ||.  A
       version matches a range if and only if every comparator in at least one
       of the ||-separated comparator sets is satisfied by the version.

       For  example,  the range >=1.2.7 <1.3.0 would match the versions 1.2.7,
       1.2.8, and 1.2.99, but not the versions 1.2.6, 1.3.0, or 1.1.0.

       The range 1.2.7 || >=1.2.9  <2.0.0  would  match  the  versions  1.2.7,
       1.2.9, and 1.4.6, but not the versions 1.2.8 or 2.0.0.

   Prerelease Tags
       If  a version has a prerelease tag (for example, 1.2.3-alpha.3) then it
       will only be allowed to satisfy comparator sets if at  least  one  com-
       parator with the same [major, minor, patch] tuple also has a prerelease

       For example, the range >1.2.3-alpha.3 would be  allowed  to  match  the
       version  1.2.3-alpha.7, but it would not be satisfied by 3.4.5-alpha.9,
       even though 3.4.5-alpha.9 is technically "greater  than"  1.2.3-alpha.3
       according  to  the  SemVer  sort rules.  The version range only accepts
       prerelease tags on the 1.2.3 version.  The version 3.4.5 would  satisfy
       the  range,  because  it  does not have a prerelease flag, and 3.4.5 is
       greater than 1.2.3-alpha.7.

       The purpose for this behavior is twofold.  First,  prerelease  versions
       frequently  are updated very quickly, and contain many breaking changes
       that are (by the author's design) not yet fit for  public  consumption.
       Therefore, by default, they are excluded from range matching semantics.

       Second,  a  user  who  has  opted  into  using a prerelease version has
       clearly indicated the intent to use that specific set of  alpha/beta/rc
       versions.   By  including  a  prerelease  tag in the range, the user is
       indicating that they are aware of the risk.  However, it is  still  not
       appropriate  to  assume that they have opted into taking a similar risk
       on the next set of prerelease versions.

   Prerelease Identifiers
       The method .inc takes an additional  identifier  string  argument  that
       will append the value of the string as a prerelease identifier:

         semver.inc('1.2.3', 'prerelease', 'beta')
         // '1.2.4-beta.0'

       command-line example:

         $ semver 1.2.3 -i prerelease --preid beta

       Which then can be used to increment further:

         $ semver 1.2.4-beta.0 -i prerelease

   Advanced Range Syntax
       Advanced  range syntax desugars to primitive comparators in determinis-
       tic ways.

       Advanced ranges may be combined in the same way as  primitive  compara-
       tors using white space or ||.

   Hyphen Ranges X.Y.Z - A.B.C
       Specifies an inclusive set.

       o 1.2.3 - 2.3.4 := >=1.2.3 <=2.3.4

       If  a partial version is provided as the first version in the inclusive
       range, then the missing pieces are replaced with zeroes.

       o 1.2 - 2.3.4 := >=1.2.0 <=2.3.4

       If a partial version is provided as the second version in the inclusive
       range,  then  all  versions  that  start with the supplied parts of the
       tuple are accepted, but nothing that would be greater than the provided
       tuple parts.

       o 1.2.3 - 2.3 := >=1.2.3 <2.4.0

       o 1.2.3 - 2 := >=1.2.3 <3.0.0

   X-Ranges 1.2.x 1.X 1.2.* *
       Any of X, x, or * may be used to "stand in" for one of the numeric val-
       ues in the [major, minor, patch] tuple.

       o * := >=0.0.0 (Any version satisfies)

       o 1.x := >=1.0.0 <2.0.0 (Matching major version)

       o 1.2.x := >=1.2.0 <1.3.0 (Matching major and minor versions)

       A partial version range is treated as an X-Range, so the special  char-
       acter is in fact optional.

       o "" (empty string) := * := >=0.0.0

       o 1 := 1.x.x := >=1.0.0 <2.0.0

       o 1.2 := 1.2.x := >=1.2.0 <1.3.0

   Tilde Ranges ~1.2.3 ~1.2 ~1
       Allows  patch-level changes if a minor version is specified on the com-
       parator.  Allows minor-level changes if not.

       o ~1.2.3 := >=1.2.3 <1.(2+1).0 := >=1.2.3 <1.3.0

       o ~1.2 := >=1.2.0 <1.(2+1).0 := >=1.2.0 <1.3.0 (Same as 1.2.x)

       o ~1 := >=1.0.0 <(1+1).0.0 := >=1.0.0 <2.0.0 (Same as 1.x)

       o ~0.2.3 := >=0.2.3 <0.(2+1).0 := >=0.2.3 <0.3.0

       o ~0.2 := >=0.2.0 <0.(2+1).0 := >=0.2.0 <0.3.0 (Same as 0.2.x)

       o ~0 := >=0.0.0 <(0+1).0.0 := >=0.0.0 <1.0.0 (Same as 0.x)

       o ~1.2.3-beta.2 := >=1.2.3-beta.2 <1.3.0 Note that prereleases  in  the
         1.2.3  version  will be allowed, if they are greater than or equal to
         beta.2.  So, 1.2.3-beta.4 would be allowed,  but  1.2.4-beta.2  would
         not,  because it is a prerelease of a different [major, minor, patch]

   Caret Ranges ^1.2.3 ^0.2.5 ^0.0.4
       Allows changes that do not modify the left-most non-zero digit  in  the
       [major,  minor,  patch]  tuple.   In other words, this allows patch and
       minor updates for versions 1.0.0 and above, patch updates for  versions
       0.X >=0.1.0, and no updates for versions 0.0.X.

       Many  authors  treat  a  0.x version as if the x were the major "break-
       ing-change" indicator.

       Caret ranges are ideal when an author may make breaking changes between
       0.2.4 and 0.3.0 releases, which is a common practice.  However, it pre-
       sumes that there will not be breaking changes between 0.2.4 and  0.2.5.
       It  allows for changes that are presumed to be additive (but non-break-
       ing), according to commonly observed practices.

       o ^1.2.3 := >=1.2.3 <2.0.0

       o ^0.2.3 := >=0.2.3 <0.3.0

       o ^0.0.3 := >=0.0.3 <0.0.4

       o ^1.2.3-beta.2 := >=1.2.3-beta.2 <2.0.0 Note that prereleases  in  the
         1.2.3  version  will be allowed, if they are greater than or equal to
         beta.2.  So, 1.2.3-beta.4 would be allowed,  but  1.2.4-beta.2  would
         not,  because it is a prerelease of a different [major, minor, patch]

       o ^0.0.3-beta := >=0.0.3-beta <0.0.4   Note  that  prereleases  in  the
         0.0.3 version only will be allowed, if they are greater than or equal
         to beta.  So, 0.0.3-pr.2 would be allowed.

       When parsing caret ranges, a missing patch value desugars to the number
       0,  but will allow flexibility within that value, even if the major and
       minor versions are both 0.

       o ^1.2.x := >=1.2.0 <2.0.0

       o ^0.0.x := >=0.0.0 <0.1.0

       o ^0.0 := >=0.0.0 <0.1.0

       A missing minor and patch values will desugar to zero, but  also  allow
       flexibility within those values, even if the major version is zero.

       o ^1.x := >=1.0.0 <2.0.0

       o ^0.x := >=0.0.0 <1.0.0

   Range Grammar
       Putting  all  this  together, here is a Backus-Naur grammar for ranges,
       for the benefit of parser authors:

         range-set  ::= range ( logical-or range ) *
         logical-or ::= ( ' ' ) * '||' ( ' ' ) *
         range      ::= hyphen | simple ( ' ' simple ) * | ''
         hyphen     ::= partial ' - ' partial
         simple     ::= primitive | partial | tilde | caret
         primitive  ::= ( '<' | '>' | '>=' | '<=' | '=' | ) partial
         partial    ::= xr ( '.' xr ( '.' xr qualifier ? )? )?
         xr         ::= 'x' | 'X' | '*' | nr
         nr         ::= '0' | ['1'-'9'] ( ['0'-'9'] ) *
         tilde      ::= '~' partial
         caret      ::= '^' partial
         qualifier  ::= ( '-' pre )? ( '+' build )?
         pre        ::= parts
         build      ::= parts
         parts      ::= part ( '.' part ) *
         part       ::= nr | [-0-9A-Za-z]+

       All methods and classes take a final loose boolean  argument  that,  if
       true, will be more forgiving about not-quite-valid semver strings.  The
       resulting output will always be 100% strict, of course.

       Strict-mode Comparators and Ranges will  be  strict  about  the  SemVer
       strings that they parse.

       o valid(v): Return the parsed version, or null if it's not valid.

       o inc(v,  release):  Return the version incremented by the release type
         (major,   premajor, minor, preminor, patch, prepatch, or prerelease),
         or null if it's not valid

       o premajor  in one call will bump the version up to the next major ver-
         sion and down to a prerelease of that major version.   preminor,  and
         prepatch work the same way.

       o If called from a non-prerelease version, the prerelease will work the
         same as prepatch. It increments the patch version, then makes a  pre-
         release.  If  the  input  version  is  already a prerelease it simply
         increments it.

       o prerelease(v): Returns an array of prerelease components, or null  if
         none exist. Example: prerelease('1.2.3-alpha.1') -> ['alpha', 1]

       o major(v): Return the major version number.

       o minor(v): Return the minor version number.

       o patch(v): Return the patch version number.

       o intersects(r1,  r2, loose): Return true if the two supplied ranges or
         comparators intersect.

       o gt(v1, v2): v1 > v2

       o gte(v1, v2): v1 >= v2

       o lt(v1, v2): v1 < v2

       o lte(v1, v2): v1 <= v2

       o eq(v1, v2): v1 == v2 This is true if  they're  logically  equivalent,
         even  if  they're not the exact same string.  You already know how to
         compare strings.

       o neq(v1, v2): v1 != v2 The opposite of eq.

       o cmp(v1, comparator, v2): Pass in a comparison string, and it'll  call
         the  corresponding  function above.  "===" and "!==" do simple string
         comparison, but are included for completeness.  Throws if an  invalid
         comparison string is provided.

       o compare(v1,  v2):  Return 0 if v1 == v2, or 1 if v1 is greater, or -1
         if  v2  is  greater.   Sorts  in  ascending  order   if   passed   to

       o rcompare(v1, v2): The reverse of compare.  Sorts an array of versions
         in descending order when passed to Array.sort().

       o diff(v1, v2): Returns difference between two versions by the  release
         type  (major,  premajor,  minor, preminor, patch, prepatch, or prere-
         lease), or null if the versions are the same.

       o intersects(comparator): Return true if the comparators intersect

       o validRange(range): Return the valid range or null if it's not valid

       o satisfies(version, range): Return true if the version  satisfies  the

       o maxSatisfying(versions,  range):  Return  the  highest version in the
         list that satisfies the range, or null if none of them do.

       o minSatisfying(versions, range): Return the lowest version in the list
         that satisfies the range, or null if none of them do.

       o gtr(version,  range):  Return true if version is greater than all the
         versions possible in the range.

       o ltr(version, range): Return true if version is less than all the ver-
         sions possible in the range.

       o outside(version,  range, hilo): Return true if the version is outside
         the bounds of the range in either the high  or  low  direction.   The
         hilo  argument  must  be  either the string '>' or '<'.  (This is the
         function called by gtr and ltr.)

       o intersects(range): Return true  if  any  of  the  ranges  comparators

       Note  that,  since ranges may be non-contiguous, a version might not be
       greater than a range, less than a range, or satisfy a range!  For exam-
       ple,  the range 1.2 <1.2.9 || >2.0.0 would have a hole from 1.2.9 until
       2.0.0, so the version 1.2.10  would  not  be  greater  than  the  range
       (because  2.0.1  satisfies,  which  is higher), nor less than the range
       (since 1.2.8 satisfies, which is lower), and it also does  not  satisfy
       the range.

       If you want to know if a version satisfies or does not satisfy a range,
       use the satisfies(version, range) function.

       o coerce(version): Coerces a string to semver if possible

       This aims to provide a  very  forgiving  translation  of  a  non-semver
       string  to  semver.  It looks for the first digit in a string, and con-
       sumes all remaining characters which satisfy at least a partial  semver
       (e.g.,  1, 1.2, 1.2.3) up to the max permitted length (256 characters).
       Longer versions are simply truncated ( becomes  4.6.3).
       All  surrounding  text  is simply ignored (v3.4 replaces v3.3.1 becomes
       3.4.0).  Only text which lacks digits will fail coercion  (version  one
       is not valid).  The maximum  length for any semver component considered
       for coercion is  16  characters;  longer  components  will  be  ignored
       (10000000000000000.4.7.4  becomes  4.7.4).   The  maximum value for any
       semver component is Integer.MAX_SAFE_INTEGER ||  (2**53  -  1);  higher
       value   components   are   invalid  (9999999999999999.4.7.4  is  likely

       See attributes(7) for descriptions of the following attributes:

       |Availability   | runtime/nodejs/nodejs-8 |
       |Stability      | Pass-thru volatile      |
       This    software    was    built    from    source     available     at
       https://github.com/oracle/solaris-userland.    The  original  community
       source   was   downloaded   from     https://github.com/nodejs/node/ar-

       Further information about this software can be found on the open source
       community website at https://github.com/nodejs/node.

                                  August 2018                        SEMVER(7)