How to add imports to REPL from command line?

问题

How can I make REPL to import packages given in commnad line?

Sample:

scala -someMagicHere "import sys.error"
scala> :imports
1) import scala.Predef._          (162 terms, 78 are implicit)
2) import sys.error               (2 terms)

scala> _

PS: It is not a duplicate. I want automated solution, not manually pasting some code every time I run REPL. Also I don't want to use SBT just for running one command in REPL after its start.

回答1:

Stick it in a file.

apm@mara:~/tmp$ scala -i imports.script
Loading imports.script...
import sys.error

Welcome to Scala version 2.10.2 (OpenJDK 64-Bit Server VM, Java 1.7.0_25).
Type in expressions to have them evaluated.
Type :help for more information.

scala> :impo
 1) import scala.Predef._          (162 terms, 78 are implicit)
 2) import sys.error               (2 terms)

Edit:

I think you get bonus points for finding or otherwise provoking or inducing a bug:

apm@mara:~/tmp$ scala -e "import sys.error"
java.lang.ClassNotFoundException: Main

回答2:

I wrote a script to automatize the command line param to file thing (based on A from som-snytt). It's tested on win 7 with MSYS, but it should work on Linux as well.

bash-3.1$ repl "import sys.error"
Loading C:\Users\xxx\AppData\Local\Temp\tmp.GgEjauEqwz...
import sys.error

Welcome to Scala version 2.10.0 (Java HotSpot(TM) Client VM, Java 1.7.0_07).
Type in expressions to have them evaluated.
Type :help for more information.
scala> :impo
 1) import scala.Predef._ (162 terms, 78 are implicit)
 2) import sys.error (2 terms)

#!/bin/bash

function crash {
    echo "Error: $1"
    exit 10
}

if [ $# -ne 1 ]; then
    echo "Script requires one parameter."
    exit 1
fi

t=$(mktemp) || crash "Unable to create a temp file."
[ ${#t} -lt 1 ] && crash "Suspiciously short file name, aborting."
trap "rm -f -- '$t'" EXIT

echo "$1" > "$t"
scala -i "$t" || crash "Something wrong with scala binary."

rm -f -- "$t"
trap - EXIT
exit

来源：https://stackoverflow.com/questions/18509116/how-to-add-imports-to-repl-from-command-line

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scala

read-eval-print-loop