I would like to execute a loop in REPL mode but I am getting a SyntaxError: expecting '('
var methods = eval(ObjC.classes.UIViewController.$methods);
for item in methods { console.log(item) }
Here is an example for iterating and invoking class methods
var UIDevice = ObjC.classes.UIDevice.currentDevice();
UIDevice.$ownMethods
.filter(function(method) {
return method.indexOf(':') == -1 /* filter out methods with parameters */
&& method.indexOf('+') == -1 /* filter out public methods */
})
.forEach(function(method) {
console.log(method, ':', UIDevice[method]())
})
Update:
var UIViewControllerInstance = ObjC.chooseSync(ObjC.classes.UIViewController)[0];
console.log('Sanity check =', UIViewControllerInstance, JSON.stringify(UIViewControllerInstance.$ownMethods, null, 2));
UIViewControllerInstance.$ownMethods
.filter(method => { return method.indexOf(':') == -1 && method.indexOf('+') == -1 })
.forEach(method => {
console.log(method, ':', UIViewControllerInstance[method]())
})
Instead of looking for UIViewController instances on the heap, you have direct access through UIApplication
take a look # https://frida.re/docs/examples/ios/
This problem is related to command line shells and not to Frida or any other REPL tool.
This is a Single command and multiple lines subject of a shell in terminals.
To solve it, all you need to do is to add "\" at the end of each line.
Example:
var methods = eval(ObjC.classes.UIViewController.$methods);\
for (item in methods) { console.log(item) }\
Related
I am writing a lexical analyzer using JFlex. When the word co is matched, we have to ignore what comes after until the end of the line (because it's a comment). For the moment, I have a boolean variable that changes to true whenever this word is matched and if an identifier or an operator is matched after co until the end of the line, I simply ignore it because I have an if condition in my Identifier and Operator token identification.
I am wondering if there is better way to do this and get rid of this if statement that appears everywhere?
Here is the code:
%% // Options of the scanner
%class Lexer
%unicode
%line
%column
%standalone
%{
private boolean isCommentOpen = false;
private void toggleIsCommentOpen() {
this.isCommentOpen = ! this.isCommentOpen;
}
private boolean getIsCommentOpen() {
return this.isCommentOpen;
}
%}
Operators = [\+\-]
Identifier = [A-Z]*
EndOfLine = \r|\n|\r\n
%%
{Operators} {
if (! getIsBlockCommentOpen() && ! getIsCommentOpen()) {
// Do Code
}
}
{Identifier} {
if (! getIsBlockCommentOpen() && ! getIsCommentOpen()) {
// Do Code
}
}
"co" {
toggleIsCommentOpen();
}
. {}
{EndOfLine} {
if (getIsCommentOpen()) {
toggleIsCommentOpen();
}
}
One way to do this is to use states in JFlex. We say that every time the word co is matched, we enter in a state named COMMENT_STATE and we do nothing until the end of the line. After the end of the line, we exit the COMMENT_STATE state. So here is the code:
%% // Options of the scanner
%class Lexer
%unicode
%line
%column
%standalone
Operators = [\+\-]
Identifier = [A-Z]*
EndOfLine = \r|\n|\r\n
%xstate YYINITIAL, COMMENT_STATE
%%
<YYINITIAL> {
"co" {yybegin(COMMENT_STATE);}
}
<COMMENT_STATE> {
{EndOfLine} {yybegin(YYINITIAL);}
. {}
}
{Operators} {// Do Code}
{Identifier} {// Do Code}
. {}
{EndOfLine} {}
With this new approach, the lexer is more simpler and it's also more readable.
I'm trying to pipe output from echo into a command using GLib's spawn_command_line_sync method. The problem I've run into is echo is interpreting the entire command as the argument.
To better explain, I run this in my code:
string command = "echo \"" + some_var + "\" | command";
Process.spawn_command_line_sync (command.escape (),
out r, out e, out s);
I would expect the variable to be echoed to the pipe and the command run with the data piped, however when I check on the result it's just echoing everything after echo like this:
"some_var's value" | command
I think I could just use the Posix class to run the command but I like having the result, error and status values to listen to that the spawn_command_line_sync method provides.
The problem is that you are providing shell syntax to what is essentially the kernel’s exec() syscall. The shell pipe operator redirects the stdout of one process to the stdin of the next. To implement that using Vala, you need to get the file descriptor for the stdin of the command process which you’re running, and write some_var to it manually.
You are combining two subprocesses into one. Instead echo and command should be treated separately and have a pipe set up between them. For some reason many examples on Stack Overflow and other sites use the Process.spawn_* functions, but using GSubprocess is an easier syntax.
This example pipes the output of find . to sort and then prints the output to the console. The example is a bit longer because it is a fully working example and makes use of a GMainContext for asynchronous calls. GMainContext is used by GMainLoop, GApplication and GtkApplication:
void main () {
var mainloop = new MainLoop ();
SourceFunc quit = ()=> {
mainloop.quit ();
return Source.REMOVE;
};
read_piped_commands.begin ("find .", "sort", quit);
mainloop.run ();
}
async void read_piped_commands (string first_command, string second_command, SourceFunc quit) {
var output = splice_subprocesses (first_command, second_command);
try {
string? line = null;
do {
line = yield output.read_line_async ();
print (#"$(line ?? "")\n");
}
while (line != null);
} catch (Error error) {
print (#"Error: $(error.message)\n");
}
quit ();
}
DataInputStream splice_subprocesses (string first_command, string second_command) {
InputStream end_pipe = null;
try {
var first = new Subprocess.newv (first_command.split (" "), STDOUT_PIPE);
var second = new Subprocess.newv (second_command.split (" "), STDIN_PIPE | STDOUT_PIPE);
second.get_stdin_pipe ().splice (first.get_stdout_pipe (), CLOSE_TARGET);
end_pipe = second.get_stdout_pipe ();
} catch (Error error) {
print (#"Error: $(error.message)\n");
}
return new DataInputStream (end_pipe);
}
It is the splice_subprocesses function that answers your question. It takes the STDOUT from the first command as an InputStream and splices it with the OutputStream (STDIN) for the second command.
The read_piped_commands function takes the output from the end of the pipe. This is an InputStream that has been wrapped in a DataInputStream to give access to the read_line_async convenience method.
Here's the full, working implementation:
try {
string[] command = {"command", "-options", "-etc"};
string[] env = Environ.get ();
Pid child_pid;
string some_string = "This is what gets piped to stdin"
int stdin;
int stdout;
int stderr;
Process.spawn_async_with_pipes ("/",
command,
env,
SpawnFlags.SEARCH_PATH | SpawnFlags.DO_NOT_REAP_CHILD,
null,
out child_pid,
out stdin,
out stdout,
out stderr);
FileStream input = FileStream.fdopen (stdin, "w");
input.write (some_string.data);
/* Make sure we close the process using it's pid */
ChildWatch.add (child_pid, (pid, status) => {
Process.close_pid (pid);
});
} catch (SpawnError e) {
/* Do something w the Error */
}
I guess playing with the FileStream is what really made it hard to figure this out. Turned out to be pretty straightforward.
Based on previous answers probably an interesting case is to use program arguments to have a general app to pipe any input on it:
pipe.vala:
void main (string[] args) {
try {
string command = args[1];
var subproc = new Subprocess(STDIN_PIPE | STDOUT_PIPE, command);
var data = args[2].data;
var input = new MemoryInputStream.from_data(data, GLib.free);
subproc.get_stdin_pipe ().splice (input, CLOSE_TARGET);
var end_pipe = subproc.get_stdout_pipe ();
var output = new DataInputStream (end_pipe);
string? line = null;
do {
line = output.read_line();
print (#"$(line ?? "")\n");
} while (line != null);
} catch (Error error) {
print (#"Error: $(error.message)\n");
}
}
build:
$ valac --pkg gio-2.0 pipe.vala
and run:
$ ./pipe sort "cc
ab
aa
b
"
Output:
aa
ab
b
cc
I want to validate input corresponding to the following grammar snippet:
Declaration:
name = ID "=" brCon=BracketContent
;
BracketContent:
decCon=DecContent (comp+=COMPARATOR content+=DecContent)*
;
DecContent:
(neg=("!"|"not"))? singleContent=VarContent (op+=OPERATOR nextCon+=VarContent)*
;
My validation looks like that:
#Check
def checkNoCycleInHierarchy(Declaration dec) {
if(dec.decCon.singleContent.reference == null) {
return
}
var names = newArrayList
var con = dec.decCon.singleContent
while(con.reference != null) {
con = getThatReference(con).singleContent
if(names.contains(getParentName(con))) {
val errorMsg = "Cycle in hierarchy!"
error(errorMsg,
SQFPackage.eINSTANCE.bracketContent_DecCon,
CYCLE_IN_HIERARCHY)
return
}
names.add(getParentName(con))
}
}
But when I test this validation with a testCaseit returns me an error message:
Expected ERROR 'raven.sqf.CycleInHierarchy' on Declaration at [-1:-1] but got
ERROR (org.eclipse.emf.ecore.impl.EClassImpl#5a7fe64f (name: Declaration) (instanceClassName: null) (abstract: false, interface: false).0) 'Error executing EValidator', offset null, length null
ERROR (org.eclipse.emf.ecore.impl.EClassImpl#5a7fe64f (name: Declaration) (instanceClassName: null) (abstract: false, interface: false).0) 'Error executing EValidator', offset null, length null
I just can't figure out what's wrong with it so I hope that someone of you might have an idea.
Greetings Krzmbrzl
You test utility tells you that the validator did not produce the expected validation error ("CycleInHierarchy").
Instead, the validator produced the error "Error executing EValidator".
Which means an exception has been thrown when your validator was executed.
It turned out it was an internal error...I'm still not exactly sure what went wrong but I have rewritten my validation method and now it works as expected.
Now the method looks like this:
enter code here#Check
def checkNoCycleInHierarchy(Declaration dec) {
if(dec.varContent.reference == null) {
//proceed only if there is a reference
return
}
var content = dec.varContent
var names = newArrayList
while(content.reference != null && !names.contains(getParentName(content))) {
names.add(getParentName(content))
content = content.reference.varContent
if(names.contains(getParentName(content))) {
val errorMsg = "Cycle in hierarchy!"
error(errorMsg,
SQFPackage.eINSTANCE.declaration_BrCon,
CYCLE_IN_HIERARCHY)
return
}
}
}
I have the suspicion that there was a problem with the usage of my "getThatReference" in this case.
Greeting Krzmbrzl
Lets say i have this code:
map = %Q{
function() {
emit(this.name, { likes: this.likes });
}
}
reduce = %Q{
function(key, values) {
var result = { likes: 0 };
values.forEach(function(value) {
if(value.likes < 0){
#{Rails.logger.error "likes are negativ" }
}
result.likes += value.likes;
});
return result;
}
}
Band.where(:likes.gt => 100).map_reduce(map, reduce).out(inline: true)
As you can see I want to record an error if the value.likes are negativ:
#{Rails.logger.error "likes are negativ" }
But this Code is executed each time I run the aggregate and not when the likes are negativ.
What can I do to throw an error in the aggregate statement?
Lets just analyze the code. Firstly:
map = %Q{
function() {
emit(this.name, { likes: this.likes });
}
}
Here a string is assigned to a variable map. Please not the %Q{} is just another way of writing "". Former is another syntax to easily define strings which have a double quote. e.g.
# pretty
%Q{He said "You are awesome"}
# not so pretty
"He said \"You are awesome\""
Next there is:
reduce = %Q{
function(key, values) {
var result = { likes: 0 };
values.forEach(function(value) {
if(value.likes < 0){
#{Rails.logger.error "likes are negative" }
}
result.likes += value.likes;
});
return result;
}
}
Here another string is assigned to a variable reduce. #{Rails.logger.error "likes are negative" } is just a regular string interpolation logging an error and returning true. So above code is equivalent to:
Rails.logger.error "likes are negative"
reduce = %Q{
function(key, values) {
var result = { likes: 0 };
values.forEach(function(value) {
if(value.likes < 0){
true
}
result.likes += value.likes;
});
return result;
}
}
You see why the logging statement is executed every time.
Next there is:
Band.where(:likes.gt => 100).map_reduce(map, reduce).out(inline: true)
This is just a simple statement using mongoid to execute a map-reduce command on the mongo server, passing map and reduce functions constructed earlier.
Note that in above code, intention is to execute ruby code in a javascript reduce function. However that is not possible, as reduce function is being executed on mongodb server and cannot execute the logging statement.
One way to handle the situation could be to reduce to a hash like {likes: 0, negative_likes: 0}, incrementing negative_likes conditionally and logging error on receiving result.
PS: it might be a better idea to use aggregation framework instead of map-reduce.
I am trying to do a simple CRUD app using Ember + Rails and I'm getting the following error when trying to go to the /workouts route.
Error while loading route: TypeError {} ember.js?body=1:415
Uncaught TypeError: Object function () {
if (!wasApplied) {
Class.proto(); // prepare prototype...
}
o_defineProperty(this, GUID_KEY, undefinedDescriptor);
o_defineProperty(this, '_super', undefinedDescriptor);
var m = meta(this), proto = m.proto;
m.proto = this;
if (initMixins) {
// capture locally so we can clear the closed over variable
var mixins = initMixins;
initMixins = null;
this.reopen.apply(this, mixins);
}
if (initProperties) {
// capture locally so we can clear the closed over variable
var props = initProperties;
initProperties = null;
var concatenatedProperties = this.concatenatedProperties;
for (var i = 0, l = props.length; i < l; i++) {
var properties = props[i];
Ember.assert("Ember.Object.create no longer supports mixing in other definitions, use createWithMixins instead.", !(properties instanceof Ember.Mixin));
for (var keyName in properties) {
if (!properties.hasOwnProperty(keyName)) { continue; }
var value = properties[keyName],
IS_BINDING = Ember.IS_BINDING;
if (IS_BINDING.test(keyName)) {
var bindings = m.bindings;
if (!bindings) {
bindings = m.bindings = {};
} else if (!m.hasOwnProperty('bindings')) {
bindings = m.bindings = o_create(m.bindings);
}
bindings[keyName] = value;
}
var desc = m.descs[keyName];
Ember.assert("Ember.Object.create no longer supports defining computed properties.", !(value instanceof Ember.ComputedProperty));
Ember.assert("Ember.Object.create no longer supports defining methods that call _super.", !(typeof value === 'function' && value.toString().indexOf('._super') !== -1));
Ember.assert("`actions` must be provided at extend time, not at create time, when Ember.ActionHandler is used (i.e. views, controllers & routes).", !((keyName === 'actions') && Ember.ActionHandler.detect(this)));
if (concatenatedProperties && indexOf(concatenatedProperties, keyName) >= 0) {
var baseValue = this[keyName];
if (baseValue) {
if ('function' === typeof baseValue.concat) {
value = baseValue.concat(value);
} else {
value = Ember.makeArray(baseValue).concat(value);
}
} else {
value = Ember.makeArray(value);
}
}
if (desc) {
desc.set(this, keyName, value);
} else {
if (typeof this.setUnknownProperty === 'function' && !(keyName in this)) {
this.setUnknownProperty(keyName, value);
} else if (MANDATORY_SETTER) {
Ember.defineProperty(this, keyName, null, value); // setup mandatory setter
} else {
this[keyName] = value;
}
}
}
}
}
finishPartial(this, m);
this.init.apply(this, arguments);
m.proto = proto;
finishChains(this);
sendEvent(this, "init");
} has no method 'find'
My code is located here: https://github.com/ecl1pse/ember-workouts
What am I doing wrong?
Edit: Upon further investigation I believe the culprit is
EmberWorkouts.WorkoutsRoute = Ember.Route.extend(
model: -> EmberWorkouts.Workout.find()
This doesn't actually return anything. How do I debug from there?
If I replace that with this
EmberWorkouts.WorkoutsRoute = Ember.Route.extend
model: -> [{title: 'hi'}, {title: 'damn'}]
The view actually renders content.
How do I get the model to collect from Rails properly?
Ember Data's interface has changed a little with the current release:
You can clear out the store.js file entirely. Ember Data will automatically set up a data store for you using the REST Adapter (unless you tell it otherwise).
Use model: -> #store.find('workout') instead.
I tested this with your app and it works.
If you haven't read through the Ember Data Guide in the last week or two (it's changed a lot), I would spend a few minutes on it.
The fix for this error (as of ember-data 1.0.0.beta.6) for me was to make sure that the JSON returned from the server included an "id" field for each model, BUT not to explicitly declare the id when setting up the Ember DS.Model.
jbuilder template:
json.scans do
json.array! #scans do |scan|
json.id scan.id # This prop has to be there
json.name scan.name
end
end
Ember model:
EmberApp.Scan = DS.Model.extend(
// Don't include the id prop here
name: DS.attr("string")
)