ProcessArgs

This structure provides access to the environment and the arguments of an OPAL Process.

Signature of ProcessArgs

List of Import References :
See BOOL
See Com
See DENOTATION
See Nat
See Option
See Seq
See Void

SIGNATURE ProcessArgs

$Date: 2010-09-30 18:24:17 +0200 (Do, 30. Sep 2010) $ ($Revision: 616 $)

IMPORT  Nat                     ONLY nat
        Void                    ONLY void 
        Seq[denotation]         ONLY seq
        Com[denotation]         ONLY com ans
        Com[seq]                ONLY com
        Com[nat]                ONLY com
        Com[seq[denotation]]    ONLY com
        Com[void]               ONLY com

NOTE: this structure replaces the structure Env in the OPAL library. All references to Env should be replaced to references to this structure, since structure Env will go away in the near future.

Process Arguments

argCount returns the number of process arguments including the process name:

FUN argCount    : com[nat]

arg(N) returns the Nth argument. Note that the 0th argument is the program name. noSuchArg tests for the failure that the nth argument doesn't exists:

FUN arg         : nat->com[denotation]
FUN noSuchArg?  : ans[denotation] -> bool

args returns the sequence of all arguments including the program name:

FUN args        : com[seq[denotation]]

shift(N) shifts the sequence of arguments attached to the running process by the specified amount N, dropping the first N arguments for subsequent calls to arg or args:

FUN shift       : nat -> com[void]

setArgs(Args) completely replaces the arguments of the running process for subsequent calls to arg or args:

FUN setArgs     : seq[denotation]       -> com[void]

Environment Variables

env returns the value of an environment variable. noSuchEnvVar tests for the failure that an environment variable of the given name doesn't exists:

FUN env         : denotation            -> com[denotation]
FUN noSuchEnvVar? : ans[denotation]     -> bool

setEnv(Var, Val) defines the value of an environment variable. If a value for Var does already exists, it will be overwritten, otherwise a new variable will be created:

FUN setEnv      : denotation ** denotation      -> com[void]

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