Language features that you really should know from day 1

Here's a fun test to see how well you know ObjectScript.

What will each of the following statements output?

write 5 * 10 + 1

write 1 + 5 * 10

write 1 + 0 / 10

write 0 && 0 = 0

write 0 = 0 && 0

write 1 && 1 = 1

write 1 = 1 && 1

write 2 && 2 = 2

write 2 = 2 && 2

write "1 APPLE" + "2 BANANAS"

write "-1" + "1-2"

write +"+-+-+-5"

write "1D7P"-1

write "1E6F"-1

write 0 = "FOO"

write 0 = +"FOO"

write 0 = ''"FOO"

write "10X" - " 5" - "5"

write "10-5"

write +"10-5"

write @"10-5"

write 5_"1"-1

write "5"-1_"1"

write 10 + 10 > 21 + 1

Scroll down to see how many you got right...

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>write 5 * 10 + 1
51
 
>write 1 + 5 * 10
60

>write 1 + 0 / 10
.1
 
>write 0 && 0 = 0
1
 
>write 0 = 0 && 0
0
 
>write 1 && 1 = 1
1
 
>write 1 = 1 && 1
1
 
>write 2 && 2 = 2
0
 
>write 2 = 2 && 2
1
 
>write "1 APPLE" + "2 BANANAS"
3
 
>write "-1" + "1-2"
0
 
>write +"+-+-+-5"
-5
 
>write "1D7P"-1
0
 
>write "1E6F"-1
999999
 
>write 0 = "FOO"
0
 
>write 0 = +"FOO"
1
 
>write 0 = ''"FOO"
1
 
>write "10X" - " 5" - "5"
5
 
>write "10-5"
10-5

>write +"10-5"
10
 
>write @"10-5"
5

>write 5_"1"-1
50

>write "5"-1_"1"
41

>write 10 + 10 > 21 + 1
1

There are a couple of things going on here that are important to understand, otherwise your logic is going to look like its doing unexpected things.

The first is that ObjectScript implements strict left to right precedence, that means ObjectScript is going to behave completely differently to other languages that you might use.

The second is the automated coercion of strings to numbers, this can be both useful and a trip hazard that you need to be aware of. I've also seen some cool and crazy ideas that leverage on this, but best stay away from doing anything too clever as it can lead to unreadable code.

Precedence and Coercion are the main points here, and if you are new to the language make sure you have a good handle on them. For more detailed information read the documentation here...

https://docs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?KEY=GCOS_operators