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GHCi: Behave nicely on `-e`, like `ghc` and other programs

Like many programming language environments, GHC offers a handy -e option for evaluating an expression, then returning to the shell.

$ ghc -e '2 + 2'

4

One would expect the interpreter, GHCi, to offer a similar flag, but it surprisingly rejects it.

ghci -e '2 + 2'

ghc: on the commandline: cannot use `--interactive' with `-e'

Usage: For basic information, try the `--help' option.

I think this behavior is quite unintuitive--when I pass -e <exp> to ghci, or pass --interactive -e <exp> to ghc, I expect the expression to be evaluated as the leading expression in an interactive interpreter session.

Could we please tweak ghc like this to make it slightly more intuitive when these flags are used together?

Trac metadata
Trac field Value
Version 7.8.2
Type FeatureRequest
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
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Related
Blocking
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Operating system
Architecture
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