nix-create-sandbox-rc generates bad shell code in the presence of exported shell functions

[twhitehead]

In the particular setup I'm working on, there is a bash exported function module which is tripping up the environment setup code

module () 
{ 
    eval `/usr/bin/modulecmd bash $*`
}
declare -fx module

It produces the following environment variable definition under printenv

BASH_FUNC_module()=() {  eval `/usr/bin/modulecmd bash $*`
}

Which gets translated into the nix-sandbox-rc-... file command

export BASH_FUNC_module()=\(\)\ \{\ \ eval\ \`/usr/bin/modulecmd\ bash\ \$\*\`'
'\}

Causing the shell to choke with the error message

/tmp/nix-sandbox-rc-26417EZN line 97 syntax error near unexpected token `('

One solution may be to have nix-create-sandbox-rc just capture and use the output of

declare -x
declare -fx

for the shell script instead of using printenv -0.

Cheers! -Tyson