opam-show(1)
NAME
opam-show - Display information about specific packages.
SYNOPSIS
opam show [OPTION]... PACKAGES...
DESCRIPTION
This command displays the information block for the selected package(s). The information block consists of the name of the package, the installed version if this package is installed in the currently selected compiler, the list of available (installable) versions, and a complete description. opam list can be used to display the list of available packages as well as a short description for each.
ARGUMENTS
PACKAGES
List of package names, with an optional version or constraint, e.g
`pkg', `pkg.1.0' or `pkg>=0.5'.
OPTIONS
-f FIELDS, --field=FIELDS
Only display these fields. You can specify multiple fields by
separating them with commas.
--raw
Print the raw opam file for this package
--where
Print the location of the opam file used for this package
COMMON OPTIONS
These options are common to all commands.
--color=WHEN (absent=auto)
Colorize the output. WHEN must be one of `always', `never' or
`auto'.
--criteria=CRITERIA
Specify user preferences for dependency solving for this run.
Overrides both $OPAMCRITERIA and $OPAMUPGRADECRITERIA. For details
on the supported language, and the external solvers available, see
http://opam.ocaml.org/doc/Specifying_Solver_Preferences.html. A
general guide to using solver preferences can be found at
http://www.dicosmo.org/Articles/usercriteria.pdf. The default value
is
-count(down),-count(removed),-notuptodate(solution),-sum(solution,version-lag),-count(new)
for upgrades, and
-count(removed),-notuptodate(request),-sum(request,version-lag),-count(down),-notuptodate(changed),-count(changed),-notuptodate(solution),-sum(solution,version-lag)
otherwise.
--cudf=FILENAME
Debug option: Save the CUDF requests sent to the solver to
FILENAME-<n>.cudf.
--debug
Print debug message to stderr. This is equivalent to setting
$OPAMDEBUG to "true".
--debug-level=LEVEL
Like `--debug', but allows specifying the debug level (`--debug'
sets it to 1). Equivalent to setting $OPAMDEBUG to a positive
integer.
--git-version
Print the git version if it exists and exit.
--help[=FMT] (default=pager)
Show this help in format FMT (pager, plain or groff).
--no-base-packages
Do not install base packages (useful for testing purposes). This is
equivalent to setting $OPAMNOBASEPACKAGES to a non-empty string.
--no-self-upgrade
OPAM will replace itself with a newer binary found at OPAMROOT/opam
if present. This disables this behaviour.
-q, --quiet
Be quiet when installing a new compiler.
--root=ROOT (absent=~/.opam)
Use ROOT as the current root path. This is equivalent to setting
$OPAMROOT to ROOT.
--safe
Make sure nothing will be automatically updated or rewritten.
Useful for calling from completion scripts, for example. Will fail
whenever such an operation is needed ; also avoids waiting for
locks, skips interactive questions and overrides the OPAMDEBUG
variable.
--solver=CMD
Specify the name of the external dependency solver. The default
value is aspcud. Either 'aspcud', 'packup' or a custom command that
may contain the variables %{input}%, %{output}% and %{criteria}%
--strict
Fail whenever an error is found in a package definition or a
configuration file. The default is to continue silently if
possible.
--switch=SWITCH
Use SWITCH as the current compiler switch. This is equivalent to
setting $OPAMSWITCH to SWITCH.
--use-internal-solver, --no-aspcud
Force use of internal heuristics, even if an external solver is
available.
-v, --verbose
Be more verbose, show package sub-commands and their output. Repeat
to see more. Repeating n times is equivalent to setting
$OPAMVERBOSE to "n".
--version
Show version information.
-y, --yes
Disable interactive mode and answer yes to all questions that would
otherwise be asked to the user. This is equivalent to setting
$OPAMYES to "true".
ENVIRONMENT VARIABLES
OPAM makes use of the environment variables listed here. Boolean
variables should be set to "0", "no" of "false" to disable, "1", "yes"
or "true" to enable.
OPAMCOLOR, when set to always or never, sets a default value for the
--color option.
OPAMCRITERIA specifies user preferences for dependency solving.The
default value is
-count(removed),-notuptodate(request),-sum(request,version-lag),-count(down),-notuptodate(changed),-count(changed),-notuptodate(solution),-sum(solution,version-lag).
See also option --criteria
OPAMCURL can be used to select a given 'curl' program. See OPAMFETCH
for more options.
OPAMDEBUG see options `--debug' and `--debug-level'.
OPAMDOWNLOADJOBS sets the maximum number of simultaneous downloads.
OPAMEXTERNALSOLVER see option `--solver'.
OPAMFETCH specifies how to download files: either `wget', `curl' or a
custom command where variables %{url}%, %{out}%, %{retries}%,
%{compress}% and %{checksum}% will be replaced. Overrides the
'download-command' value from the main config file.
OPAMJOBS sets the maximum number of parallel workers to run.
OPAMLOCKRETRIES sets the number of tries after which OPAM gives up
acquiring its lock and fails. <= 0 means infinite wait.
OPAMNO answer no to any question asked.
OPAMNOASPCUD see option `--no-aspcud'.
OPAMNOSELFUPGRADE see option `--no-self-upgrade'.
OPAMPINKINDAUTO if set, version control systems are detected when
pinning to a local path.
OPAMREQUIRECHECKSUMS see option `--require-checksums'.
OPAMRETRY sets the number of tries before failing downloads.
OPAMROOT see option `--root'. This is automatically set by `opam config
env --root=DIR' when DIR is non-default or OPAMROOT is already defined.
OPAMSAFE see option `--safe'
OPAMSKIPVERSIONCHECKS bypasses some version checks. Unsafe, for
compatibility testing only.
OPAMSOLVERTIMEOUT change the time allowance of the internal solver.
OPAMSTATUSLINE display a dynamic status line showing what's currently
going on on the terminal. (one of one of `always', `never' or `auto')
OPAMSWITCH see option `--switch'. Automatically set by `opam config env
--switch=SWITCH'.
OPAMUPGRADECRITERIA specifies user preferences for dependency solving
when performing an upgrade. Overrides OPAMCRITERIA in upgrades if both
are set.The default value is
-count(down),-count(removed),-notuptodate(solution),-sum(solution,version-lag),-count(new).
See also option --criteria
OPAMUSEINTERNALSOLVER see option `--use-internal-solver'.
OPAMUTF8 use UTF8 characters in output (one of one of `always', `never'
or `auto'). By default `auto', which is determined from the locale).
OPAMUTF8MSGS use extended UTF8 characters (camels) in OPAM messages.
Implies OPAMUTF8. This is set by default on OSX only.
OPAMVAR_var overrides the contents of the variable var when
substituting `%{var}%` strings in `opam` files.
OPAMVAR_package_var overrides the contents of the variable package:var
when substituting `%{package:var}%` strings in `opam` files.
OPAMVERBOSE see option `--verbose'.
OPAMYES see option `--yes'.
FURTHER DOCUMENTATION
See https://opam.ocaml.org.
AUTHORS
Thomas Gazagnaire <thomas@gazagnaire.org> Anil Madhavapeddy <anil@recoil.org> Fabrice Le Fessant <Fabrice.Le_fessant@inria.fr> Frederic Tuong <tuong@users.gforge.inria.fr> Louis Gesbert <louis.gesbert@ocamlpro.com> Vincent Bernardoff <vb@luminar.eu.org> Guillem Rieu <guillem.rieu@ocamlpro.com> Roberto Di Cosmo <roberto@dicosmo.org>
BUGS
Check bug reports at https://github.com/ocaml/opam/issues.
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