167 lines
6.3 KiB
Plaintext
167 lines
6.3 KiB
Plaintext
The Scheme Underground Expect package
|
|
Designed and implemented by David Fisher and Olin Shivers
|
|
|
|
(spawn* THUNK) -> task procedure
|
|
|
|
Spawn* forks a process to execute THUNK, and returns a task data-structure
|
|
that contains all of the information that expect-package elements need in
|
|
order to interact with that process.
|
|
|
|
(spawn . EPF) -> task procedure
|
|
|
|
This is syntactic sugar for (spawn* (lambda () (exec-epf EPF))).
|
|
Spawns the epf.
|
|
|
|
(ports->task INPUT-PORT OUTPUT-PORT) -> task procedure
|
|
|
|
This procedure constructs a task from a pair of ports.
|
|
|
|
(task:in TASK) -> output-port procedure
|
|
(task:out TASK) -> input-port procedure
|
|
(task:process TASK) -> process procedure
|
|
|
|
These three procedures return, in order, the input port that can be used to
|
|
get data from the task, the output port that can be used to send data to the
|
|
task, and the process that the task is running.
|
|
|
|
(task:pre-match TASK) -> string procedure
|
|
(task:buf TASK) -> string procedure
|
|
|
|
When an EXPECT pattern matches some input, the task:pre-match field is set to
|
|
the string preceding the matched data, and the task:buf field is set to the
|
|
string coming after the matched data, that is, it saves input that hasn't
|
|
yet been processed. When EXPECT starts, it first considers any data stored
|
|
in the task:buf field.
|
|
|
|
(set-task:pre-match TASK STR)
|
|
(set-task:buf TASK STR)
|
|
...
|
|
|
|
-------------------------------------------------------------------------------
|
|
(EXPECT [<name> <loop-var-inits>] <eclause> ...) -> values syntax
|
|
|
|
<eclause> ::= (<task> <aclause> ...) [Task clause.]
|
|
| <option-clause>
|
|
| (ON-TIMEOUT <body> ...) [Do on timeout.]
|
|
|
|
Action clauses:
|
|
<aclause> ::= (ON-EOF <body> ...) [Do on EOF.]
|
|
| (<pattern> <matchvars> <exp> ...) [Do if pattern matches.]
|
|
| (TEST . <cond-clause>)
|
|
|
|
<matchvars> ::= () [No match info]
|
|
| (<matchvar>) [Match struct only]
|
|
| (<matchvar> <submatch-var0> ...) [...also submatch strings.]
|
|
|
|
<option-clause> ::= (OPTION <option> ...)
|
|
<option> ::= (TIMEOUT <nsecs>)
|
|
| (ECHO <bool>) ; Not supported
|
|
| (MAX-SIZE <nchars>) ; Not supported
|
|
| (MONITOR <proc>)
|
|
|
|
Expect takes a number of tasks, and waits for a number of patterns to
|
|
be output by these tasks. When expect sees a pattern for which it has been
|
|
waiting, it executes the appropriate list of commands. The two types of
|
|
expect clauses are option clauses and task-pattern clauses.
|
|
|
|
Option clauses take the form (OPTION <option> ...)
|
|
where an <option> is one of
|
|
(TIMEOUT <nsecs>) This controls how long expect waits for the patterns
|
|
before timing out. The lowest timeout clause
|
|
determines when the entire expect form will time out.
|
|
A timeout value of #f means no timeout. The default
|
|
value is ... seconds.
|
|
|
|
(MONITOR <proc>) This hook establishes a monitor procedure for the
|
|
the expect processing. A monitor is a procedure
|
|
of one argument, that is applied when various
|
|
events occur:
|
|
#F EOF
|
|
regexp Match occurred.
|
|
string New input arrived.
|
|
This string will not span a match.
|
|
That is, if new input arrives and
|
|
is matched, then we only report the
|
|
new input up to the end of the match.
|
|
The rest of the input is saved in the
|
|
task's push-back buffer and is not reported.
|
|
'timeout EXPECT timed out.
|
|
|
|
An action clause <aclause> can be one of
|
|
(<pattern> <matchvars> <body> ...)
|
|
If the pattern matches input read from the task, expect binds the
|
|
match vars and then executes the body forms. The value of the whole
|
|
EXPECT form is the value produced by the last body form. The match
|
|
vars list is of the form
|
|
([<match-var> [<sub-match-var0> ... <sub-match-varN>]])
|
|
<match-var> is bound to the regexp match structure. <sub-match-varI>
|
|
is bound to the string corresponding to the regexp's Ith sub-match
|
|
(where sub-match 0 is the string for the whole match). Any of these
|
|
variables may be #F instead of an identifier, meaning a "don't-care"
|
|
binding.
|
|
|
|
(on-eof EXPRESSION ...)
|
|
If EXPECT hits EOF on the task without finding a match, this clause
|
|
is triggered. If EXPECT hits EOF and there is no ON-EOF clause for
|
|
the task, nothing happens.
|
|
|
|
(test . COND-CLAUSE)
|
|
This allows for general conditionals to be placed into the
|
|
EXPECT form.
|
|
|
|
-------------------------------------------------------------------------------
|
|
(INTERACT <task> <iclause> ...) syntax
|
|
|
|
Interact allows the user to interact with a running task, relaying the
|
|
keys pressed by the user to the task and outputting the characters
|
|
provided by the task to the user. If clauses are provided by the
|
|
programmer, interact will filter input before passing it along to the
|
|
task. A clause is either a character-clause or a filter-clause.
|
|
|
|
(<character> <continuation-variable> <body> ...)
|
|
When interact matches the character, it bind the continuation variable
|
|
to the continuation out of the interaction, then evaluates the clause
|
|
body.
|
|
|
|
(FILTER <procedure>)
|
|
Where filter is passed two variables, the character input and the
|
|
continuation out of the interaction. In both cases, if the clause
|
|
returns true, it falls through to the next clause. If all clauses
|
|
fall through, the character is passed on to the task. However, the
|
|
continuation still needs to be called in order to break out of the
|
|
interaction.
|
|
|
|
Example: (filter (lambda (c k)
|
|
(if
|
|
|
|
(send STRING TASK) -> (undefined) procedure
|
|
|
|
Send sends the string to the task, as if a user had typed it.
|
|
|
|
(close-task TASK) -> (undefined) procedure
|
|
|
|
Close-task closes all input and output ports corresponding to the indicated
|
|
task.
|
|
|
|
(wait-task TASK) -> (undefined) procedure
|
|
|
|
Wait-task waits for the indicated task to complete, reaping the task.
|
|
|
|
-------------------------------------------------------------------------------
|
|
Tty-Mung Package
|
|
|
|
(modify-tty-info PROC [PORT]) procedure
|
|
|
|
Modify-tty-info applies PROC to either the tty-info of the current
|
|
input port, or the indicated PORT, changing the state of the terminal.
|
|
There are five procedures provided to use with modify-tty-info:
|
|
|
|
echo-off Turns terminal echoing off.
|
|
echo-on Turns terminal echoing on.
|
|
raw Puts the terminal into raw mode. Raw-initialize _must_
|
|
be used after raw for it to work right.
|
|
raw-initialize Initializes the min and time fields of a raw terminal.
|
|
canonical Puts the terminal into raw mode.
|
|
|
|
|