Error "command not found" after installing go-eval - macos

Question

I'm trying to run Go in an interactive mode.
I want to use go-eval for that, I followed their README instructions:
I ran go get github.com/sbinet/go-eval/ successfully
I ran go-eval which resulted in -bash: go-eval: command not found
Some more information:
echo $PATH returns: /usr/local/go/bin:...
echo $GOPATH returns: $HOME/golang
running whereis go-eval returns no output
running go install go-eval returns:
can't load package: package go-eval: cannot find package "go-eval" in any of:
/usr/local/go/src/go-eval (from $GOROOT)
$HOME/golang/src/go-eval (from $GOPATH)

Answer 1

You'll need to add GOPATH/bin to PATH.
PATH="$GOPATH/bin:$PATH"
Update [Go 1.8 and above]: GOPATH will default to $HOME/go. The above will not work if GOPATH is not explicitly set.
To set both, add this to your .profile file:
export GOPATH="$HOME/go"
PATH="$GOPATH/bin:$PATH"

Answer 2

Ran into this issue while using export PATH="~/go/bin:$PATH".
Seems the ~ was causing problems and changing to the full path worked.
Try something like this instead, which won't use a tilde:
export PATH="$HOME/go/bin:$PATH"

Answer 3

Is the binary go-eval in $GOPATH/bin? Are you running the command with $GOPATH/bin/ as your working directory? If not, thats likely the problem.
go get & go install installs go binaries (if any) in $GOPATH/bin
Check $GOPATH/bin for the go-eval binary. If its there, try running it from $GOPATH/bin with ./go-eval. If that works, you're good.
In future, if you wish to run go binaries found in $GOPATH/bin from anywhere in your shell, add the following to your .bashrc or profile:
export PATH=$PATH:$GOPATH/bin
Then restart your terminal or run . ~/.bashrc or . /etc/profile
When running go install go-eval I get:
can't load package: package go-eval: cannot find package "go-eval" in any of:
/usr/local/go/src/go-eval (from $GOROOT)
$HOME/golang/src/go-eval (from $GOPATH)
You get the above error because go-eval is not in $HOME/golang/src/go-eval. Running go get github.com/sbinet/go-eval/ will download the source to $GOPATH/src/github/sbinet/go-eval/. If you want to run go install go-eval, you have to specify the package name relevant to its position in the directory hierarchy in $GOPATH/src.
e.g.
go install github/sbinet/go-eval

Answer 4

I'd like to add this in addition to the answers given.
As a helpful tip, uou can always test your commands with the which command.
Such as: which go
If the command is not found, you know you have a PATH problem you need to address first.
Then you can focus on finding the command with the find command.
Such as: find / -name "go" -print 2>/dev/null
The first slash is the directory to start the search, the argument to the -name is the command you're looking for and the -print gets a good results look. the 2>/dev/null sends results of directories that are not accessible to neverland (null) so that you do not need to see a bunch of errors.
Using this process helps you quickly find the command in question and then you can add it to your PATH env variable and it becomes accessible as stated in the other answers.

Answer 5

All above answers are self explaining. Over and above those I would like to add that by default you can access only those commands from terminal without path to binary whose bin folder is added to the environment variable, be it linux, mac or windows.
Else you will have to specify the path to bin folder of that software followed by the binary name. For instance in your case <path_to_bin_folder>/go-eval.
This is the most common reason that you are not able to execute that command directly from the command line. Please remember this and try this before searching for answers online because this will most probably solve your issue. All you have to know is the installation path.
So, write the following into the rc or profile file for your terminal and save, example for zsh it is ~/.zshrc, for bash it is ~/.bash_profile or ~/.bash_rc.
export GOPATH="$HOME/go"
export PATH=$PATH:$GOPATH/bin
Now although the file is saved but the changes will not reflect immediately. You have to source the profile file as mentioned above. For this type source ~/.zshrc. You should now be able to run the command directly from command line now. Even if the problem still persists try quit the terminal session and logging off and then logging in.
In case you want to add path to bin folder for other packages, you can append it to the $PATH environment variable using :. So for example if you want to add path to java binary as well, then just do
export PATH=$PATH:$JAVA_HOME/bin
Also it is a good practice to define the path to root folder of a package in its separate environment variable(example $GOPATH="$HOME/go"). In case if the installation path changes in future then you'll just have to update the environment variable related to that binary (example just update, $GOPATH="newpath") and your command will work as previously, since the change in $GOPATH will reflect in $PATH.

Answer 6

add those line in to ~/.zshrc
export GOPATH="$HOME/go"
export PATH=$PATH:$GOPATH/bin
run source ~/.zshrc