I'm working with an API that returns an array of objects. I can get all the keys, but two of those have numbers as keys, and I cannot get it. Give me an error.
I really dont know why I can not get it those keys.
Is there something different due to are numbers?
BTW Im using axios.
If you're using dot notation, you should change to bracket notation to access properties start by a number.
The code below uses dot notation, it throws an error
const test = {"1h" : "test value"};
console.log(test.1h); // error
Why :
In the object.property syntax, the property must be a valid JavaScript
identifier.
An identifier is a sequence of characters in the code that identifies a variable, function, or property.
In JavaScript, identifiers are case-sensitive and can contain Unicode letters, $, _, and digits (0-9), but may not start with a digit.
The code below uses bracket notation, works fine
const test = {"1h" : "test value"};
console.log(test["1h"]); // works
Why :
In the object[property_name] syntax, the property_name is just a
string or Symbol. So, it can be any string, including '1foo', '!bar!',
or even ' ' (a space).
Check out the document here
Related
I have a string of numbers set by user. Defined in the beginning of the Webdriver test:
numbers = input("prompt")
Then I need to enter value of this variable by JS code like this:
driver.execute_script("document.getElementsByName('phone')[0].value=***")
Where instead of *** I need the value of "numbers" variable. How should I properly insert it to make it work?
Here is what you want to do.
numbers = input("prompt")
driver.execute_script("document.getElementsByName('phone')[0].value={}".format(numbers))
The documentation link:
https://docs.python.org/3/library/string.html
And a snip-it from the docs:
The field_name itself begins with an arg_name that is either a number or a keyword. If it’s a number, it refers to a positional argument, and if it’s a keyword, it refers to a named keyword argument. If the numerical arg_names in a format string are 0, 1, 2, … in sequence, they can all be omitted (not just some) and the numbers 0, 1, 2, … will be automatically inserted in that order. Because arg_name is not quote-delimited, it is not possible to specify arbitrary dictionary keys (e.g., the strings '10' or ':-]') within a format string. The arg_name can be followed by any number of index or attribute expressions. An expression of the form '.name' selects the named attribute using getattr(), while an expression of the form '[index]' does an index lookup using getitem().
Changed in version 3.1: The positional argument specifiers can be omitted for str.format(), so '{} {}'.format(a, b) is equivalent to '{0} {1}'.format(a, b).
OR
numbers = input("prompt")
driver.execute_script("document.getElementsByName('phone')[0].value=%s" % numbers)
See examples of both here:
https://pyformat.info/
If your python variable's value is simple string without single quotes or special characters, you can simply use:
driver.execute_script("document.getElementsByName('phone')[0].value='" +
python_variable + "'");
If it has quote marks in it, or special characters that need escaping, or if it's not a string at all, you need to obtain JavaScript string representation of your Python variable's value. json.dumps will handle all the necessary formatting and escaping for you, appropriate to the type of your variable:
from json import dumps
driver.execute_script("document.getElementsByName('phone')[0].value=" +
dumps(python_variable))
JavaScript contains the following syntax:
`hello ${name}`
I'm wondering how a Ragel machine would split the syntax above. The way I see it, the type of the closing curly brace depends on the parsing state. For example, in the code below the curly brace is instead part of the string token, since the ${ token isn't there:
`hello name}`
Finally, it becomes more tricky when you consider that the right curly can also be found within the variable expression itself, ie:
`hello ${() => { return name }()}`
How would a similar context-dependent grammar be implemented with Ragel?
The syntax inside of `` is not normally something you would handle with your lexical analyzer. Better to send it to your parser as a sequence of literal text and/or tokens. So you'd send "`" as opening, "hello " as some literal text, then the tokens "(", ")" etc. To know when to stop and go back to literal text you either need some feedback from your parser to to your scanner, or inside the scanner you need to balance the parens.
Note I've never actually made a parser for javascript, just going on what you provided above.
Why velocity gives the following output for the string
VelocityContext vc = new VelocityContext();
vc.put("foo", "bar");
String inString = "THis is ${{foo}} and this is ${foo}.Hello and ${foo}-Hello";
StringWriter sw = new StringWriter();
ve.evaluate(vc, sw, "Tag", inString);
Output:
THis is ${{} and this is bar.Hello and bar-Hello
I was expecting it would either print ${{foo}} or {bar}, why ${{}? Would double curly act as escape character?
I'm using this under strict reference mode set as true. And I neither see an exception nor I see it print it as is and that's what is confusing me.
Well, you made me look into the code and I'm not sure if I understood it correctly. The problem seems to be that in ${...}, the xxx is treated as an ASTReference, which then gets tokenized differently than a standalone string "{bar}". Specifically, it get tokenized into 3 tokens {, bar and }. Then the engine tries to find the so-called root of the reference (in ${x}, the root is x), does not recognize the pattern and goes into a fallback reference type RUNT, which says that the first token, i.e. "{" matters. This way "{bar}" becomes "{".
In other words, the expression ${{bar}} does not make sense and Velocity fails to throw an error here. In other nonsensical combinations like ${[bar]} it actually throws an error.
Velocity Variables or VTL Identifier
Must start with an alphabetic character (a .. z or A .. Z). The rest of the characters are limited to the following types of characters:
alphabetic (a .. z, A .. Z)
numeric (0 .. 9)
hyphen ("-")
underscore ("_")
You are using Formal Reference Notation as ${varName}
${{foo}} - so velocity try to get variable {foo} which is invalid VTL Identifier so it doesn't try to load the variable.
It probably then try to reference it as a JSON map {"a":"b"} and failed again, probably only { is accepted, so you remain with:
${{}
I tested your template in new velocity 2.0 and this issue isn't reproduce (in strict or non strict mode)
Output:
THis is ${{foo}} and this is bar.Hello and bar-Hello
So you have now a reason to upgrade to velocity 2.0.
I am writing some Velocity Script as part of a Marketo email template that requires that I check if an boolean attribute on a lead is set or not.
When I attempt to display something associated with a lead in my system I can do something like;
{{lead.myName}}
This also works for fields that have spaces in them;
{{lead.my name}}
When it comes to using that field for #setting or #ifing something then it doesn't work as well.
#if($lead.my name) throws an error saying that an unexpected space has been found.
I have tried variants like #if(${lead.my name}) to no avail.
Any help / pointers would be massively helpful.
Actual use case
In my example the field I need to access is called lead.Subscribed to Innovation (L) 1, I don't think the brackets will cause a problem, certainly any error messages have been space related.
According to User Guide variables cannot have spaces
A VTL Identifier must start with an alphabetic character (a .. z or A .. Z). The rest of the characters are limited to the following types of characters:
alphabetic (a .. z, A .. Z)
numeric (0 .. 9)
hyphen ("-")
underscore ("_")
even with the curly brackets :
this is valid:
#set( ${myemail} = "email#email.com" )
while trhis is invalid:
#set( ${my email} = "email#email.com" )
My best guess will be to change the source system to comply with the velocity naming convention.
I have a string data which I need to parse into a dictionary object. Here is my code:
NSString *barcode = [NSString stringWithString:#"{\"OTP\": 24923313, \"Person\": 100000000000112, \"Coupons\": [ 54900012445, 499030000003, 00000005662 ] }"];
NSLog(#"%#",[barcode objectFromJSONString]);
In this log, I get NULL result. But if I pass only one value in Coupons, I get the results. How to get all three values ?
00000005662 might not be a proper integer number as it's prefixed by zeroes (which means it's octal, IIRC). Try removing them.
Cyrille is right, here is the autoritative answer:
The application/json Media Type for JavaScript Object Notation (JSON): 2.4 Numbers
The representation of numbers is similar to that used in most programming languages. A number contains an integer component that may be prefixed with an optional minus sign, which may be followed by a fraction part and/or an exponent part.
Octal and hex forms are not allowed. Leading zeros are not allowed.