So lets say I had a chained sequence like the following:
let amount = _
.chain(selectedItemsArray)
.map(item => _.find(availableItems, {id: item.id})
//how can I determine that ALL items were found right here?
.filter('price_money')
...
Note the comment in the code above. It could be possible that the selectedItemsArray is out of date, so some selected items might not be in availableItems. So, my initial thought was to use a .tap or .thru (probably tap) to do something like _.every(selectedItems, _.isObject) or something similar to catch the error state where not all items are found and throw an error if not all items were found. This feels odd though...any better ways of handling this type of error checking mid sequence?
Something like this does work (at least I can throw an error), but seems like I'm using tap for something it's not intended for:
.tap(items => {
if (!_.every(items, _.isObject)) throw new Error('Some selected items are no longer available');
})
You can use another _.filter to check if the element is not an object, and also handle the offending value. You can use || to execute fallback code. See this question.
If you want your code to crash and burn on the first failure, use a function that throws an error instead of using console.error.
var available = [
{ id: 1, amount: 2.00 },
{ id: 2, amount: 4.00 }
];
var selected = [1, 2, 3];
var amount = _(selected)
.map(item => _.find(available, {id:item}) || item)
.filter(item => _.isObject(item) || console.error("Item not available:", item))
.sumBy('amount');
console.log("Amount:", amount.toFixed(2));
<script src="https://cdn.jsdelivr.net/lodash/4.15.0/lodash.min.js"></script>
Related
My use case is to allow the user to select a ticker from a long list of about 8000 companies. I fetch all the companies when the component mounts, so I don't really need the async feature of react-select. The problem really is displaying and scrolling through the 8000 items (as described in several open issues like this one).
My thought is why display 8000 entries when the user can't do anything meaningful with such a big list anyway. Instead why not show a maximum of 5 matches. As the user types more, the matches keep getting better. Specifically:
When the input is blank, show no options
When the input is a single character, there will still be hundreds of matches, but show only the first 5
As the user keeps on typing, the number of matches will reduce, but still limited to 5. However they will be more relavant.
I am not seeing this solution mentioned anywhere, so was wondering if it makes sense. Also wanted to find out what's the best way to implement it with react-select. I have tried the following two approaches - can you think of a better way:
Approach 1: Use Async React Select
Although I don't need async fetching, I can use this feature to filter down the options. It seems to work very well:
const filterCompanies = (value: string) => {
const inputValue = value.trim().toLowerCase();
const inputLength = inputValue.length;
let count = 0;
return inputLength === 0
? []
: companies.filter(company => {
const keep =
count < 5 &&
(company.ticker.toLowerCase().indexOf(inputValue) >= 0 ||
company.name.toLowerCase().indexOf(inputValue) >= 0);
if (keep) {
count += 1;
}
return keep;
});
};
const promiseOptions = (inputValue: string) =>
Promise.resolve(filterCompanies(inputValue));
return (
<AsyncSelect<Company>
loadOptions={promiseOptions}
value={selectedCompany}
getOptionLabel={option => `${option.ticker} - ${option.name}`}
getOptionValue={option => option.ticker}
isClearable={true}
isSearchable={true}
onChange={handleChange}
/>
);
Approach 2: Use filterOption
Here I am using the filterOption to directly filter down the list. However it does not work very well - the filterOption function is very myopic - it gets only one candidate option at a time and needs to decide if that matches or not. Using this approach I cannot tell whether I have crossed the limit of showing 5 options or not. Net result: with blank input I am showing all 8000 options, as user starts typing, the number of options is reduced but still pretty large - so the sluggishness is still there. I would have thought that filterOption would be the more direct approach for my use case but it turns out that it is not as good as the async approach. Am I missing something?
const filterOption = (candidate: Option, input: string) => {
const { ticker, name } = candidate.data;
const inputVal = input.toLowerCase();
return (
ticker.toLowerCase().indexOf(inputVal) >= 0 ||
name.toLowerCase().indexOf(inputVal) >= 0
);
};
return (
<ReactSelect
options={companies}
value={selectedCompany}
filterOption={filterOption}
getOptionLabel={option => `${option.ticker} - ${option.name}`}
getOptionValue={option => option.ticker}
isClearable={true}
isSearchable={true}
onChange={handleChange}
/>
);
you can try using react-window to replace the menulist component
ref : https://github.com/JedWatson/react-select/issues/3128#issuecomment-431397942
First, I had this: parts = parts.filter(part => part.id !== change.doc.id);
So, data is an Array and it gets 'clobbered' with a new 'filtered' Array.
Vue didn't seem keen on detecting the change and updating my DOM.
So, I saw this. Specifically: To deal with caveat 2, you can use splice:
I refactored (or is it 'de-factored' b/c my code 'grew'?) to this:
// Get index of part removed
const index = parts.forEach((part, i) => {
if (part.id === change.doc.id) {
return i;
}
});
parts.splice(index, 1);
She works...but really? Do I have to do this way? 😬
parts.splice(parts.findIndex(part => part.id === change.doc.id), 1);
I got the splice in there while still keeping as 1 line, so m happy! 🤓
I was building my project for Windows and everything was working fine. Now I started building it in HTML5 and I'm getting an error with map iterators:
for (entryMap in mapStruct.map)
{
var array:Array<Dynamic> = entryMap;
var keyObj = getJSONField(array[0], mapStruct.keyType);
var valueObj = getJSONField(array[1], mapStruct.valueType);
map.set(keyObj, valueObj);
}
And I get this error:
Exception name: TypeError: mapStruct.map.iterator is not a function
My project was working fine for Windows, but I don't know what to do, I need to use map like this.
I was trying to guess what is mapStruct without any success.
It looks like your aren't looping on a map in the right way...
Let's see some examples:
var map = ["hello" => 1, "world" => 4];
for (value in map)
{
trace('value: $value');
}
returns:
value: 1
value: 4
Here you have the link to try it online.
On the other hand, if you want to get either key and value, you should iterate it this way:
var map = ["hello" => 1, "world" => 4];
for (key in map.keys())
{
trace('key: $key value: ${map[key]}');
}
* Note the keys method call
And it returns:
key: hello value: 1
key: world value: 4
Here's the 'Try Haxe' link for it
if I knew which type mapStruct is, I'd probably help you more
I'm writing tests for Vue.js and I'm trying to write the test to ensure that when some props are changed for pagination, the resulting values within the component are updated properly.
So when I console.log the component, I see the correctly updated values, but then when I try to literally grab that attribute it gives me the old and outdated value. Look at rangeList in the following screenshot to see what I mean:
Here is my code so that you see how what is generating this output.
pagComp.$refs.component.limit = 10;
pagComp.$refs.component.pages = 145;
console.log(pagComp.$refs.component);
console.log('RangList: ' + pagComp.$refs.component.rangeList.length);
Here is the code that modifies rangeList:
createListOfRanges() {
let range = [];
for(let i = 0; i < this.pages; i++) {
range.push(i);
}
this.rangeList = [];
while(range.length > 0) {
this.rangeList.push(range.splice(0, this.rangeLength));
}
this.correctLastRange();
},
Finally, there are two places this function is called: when the component is being created, and when the pages attribute changes. Here is the watcher:
watch: {
pages(val) {
this.createListOfRanges();
}
},
I see some issues with this part of your code:
while(range.length > 0) {
this.rangeList.push(range.splice(0, this.rangeLength));
}
range.splice(..) returns an array, which is getting pushed into this.rangeList
Forget about that for a minute. Look at the following example:
x = [1, 2, 3, 4]
x.splice(0, 2) // result: [1, 2]
As you can see above, splice returns an array, not an element. Now, in the same example above:
x = [1, 2, 3, 4]
y = [10, 11]
y.push(x.splice(0, 2))
Check the value of y. It will be [10, 11, [1, 2] ]. It is an array within another array. It does not look very meaningful here. You can do the above x and y experiments directly in your developer console.
In your case, your x happens to be the local range array within createListOfRanges method, and your y is this.rangeList that belongs to your Vue component.
Can you check your app logic at around that area, and see if that is really what you want to do?
For debugging Vue.js apps, you also need Vue devtools: https://github.com/vuejs/vue-devtools - it is much better than console.log()
While #Mani is right on the line of code giving you issues is your push to rangeList.
createListOfRanges() {
let range = [];
for(let i = 0; i < this.pages; i++) {
range.push(i);
}
this.rangeList = [];
while(range.length > 0) {
this.rangeList.push(range.splice(0, this.rangeLength));
}
this.correctLastRange();
},
pushing the result of the splice just makes a single element with all the elements of range in it.
try changing it to
this.rangeList.push(range.shift());
Though your function could be simplified by pushing the for(let i = 0; i < this.pages; i++) { i value directly to rangeList unless that's a simplification.
This JSFiddle shows what I'm talking about.
I appreciate the answers above, however they aren't what the issue was.
The problem was with Vue's lifecycle. I'm not 100% sure why, but when the page and limit variables are changed it takes another moment for the page watcher (shown above) to get executed and update the component. So thus it wouldn't show up in my tests. So what I did was use nextTick like so, which fixed the problem.
pagVue.limit = 10; // limit and pages change together every time automatically
pagVue.pages = 145;
Vue.nextTick(() => {
expect(pagination.rangeList.length).toBe(25);
})
I have a dijit.form.NumberTextBox input field that starts out with these parms:
new dijit.form.NumberTextBox({
id: din1,
style: "width:60px",
constraints: {
places: 0,
pattern: '######'
}
},
din1);
Everything works great..My question is I would like to change 'places' and 'pattern' parms on the fly. So I wrote this to change 'places' and 'patterns' parms:
var myFldObj = dijit.byId(din1);
if (myFldObj) {
var myConstObj = myFldObj.attr('constraints');
if (myConstObj) {
myConstObj.places = 2;
myConstObj.pattern = '#####.0';
}
}
So, after I show the form again, I'd expect the entry field to allow 2 decimal places but the form still acts like places=0 and pattern='######'. When I check the values of 'places' and 'pattern' I get what I'd expect (2 and #####.0). My question:
Can you change these values on the fly??
OR
Do you have to destroy the original dijit object and recreate with new parms??
Thx!!
So, here is what worked for me:
First, I think this is a bug because an input field that starts out like
new dijit.form.NumberTextBox({
id: "fieldID",
style: "width:60px",
constraints: {
places: 0
}
},
"fieldID");
that is then changed on the fly with code like:
NOTE: ntbArry - Array of dijit.form.NumberTextBox objs tied to a html
input tag id.
for (var x=0;x < ntbArry.length;x++) {
var handle = ntbArry[x];
if (handle) {
handle.attr('constraints').places = 2;
handle.attr('constraints').pattern = '#####.0#';
}
}
Does not exhibit the same behavior as a field created this way (no constraints mods on the fly):
new dijit.form.NumberTextBox({
id: "fieldID",
style: "width: 60px",
constraints: {
places: 2,
pattern: '#####.0#'
}
},
"fieldID");
It's close in behavior but every time you type a decimal point, the error message pops up stating invalid entry. This message doesn't pop up when typing the decimal point on a field that was originally created with the constraints places=2 and pattern '#####.0#'.
So, to get original behavior I wanted:
fieldIDEvents is an array of dojo events tied to NumberTextBox fields.
Before continuing disconnect dojo events
for (var x=0;x < fieldIDEvents.length;x++) {
var handle = fieldIDEvents[x];
if (handle) {
dojo.disconnect(handle);
}
}
then destroy the NumberTextBox dojo objects
for (var x=0;x < ntbArry.length;x++) {
var handle = ntbArry[x];
if (handle) {
handle.destroy();
ntbArry[x] = null;
}
}
Next, place the input tag back into the html because it gets destroyed:
NOTE: tdtag and an id on a html td tag which should contain the input tag.
var fld1 = this.document.getElementById("tdtag");
if (fld1) {
//alert("\""+fld1.innerHTML+"\"");
fld1.innerHTML = "<input id=\"fieldID\">";
}
Now, create the NumberTextBox object again:
ntbArry[0] = new dijit.form.NumberTextBox({
id: "fieldID",
style: "width: 60px",
constraints: {
places: 2,
pattern: '#####.0#'
}
},
"fieldID");
It's a few extra steps but, at least I know this is what works for me..If I'm missing something basic, let me know, it's easy to miss the small details with this stuff.
I use Dojo 1.3 and I can see that dijit.form.NumberTextBox has no pattern and places properties, but has editOptions property. So I would try to change the constraints like this:
myConstObj.editOption.places = 2;