Expression Legend
You can decide to model your decisions in two ways: either by using natural language or by using the language defined by the DMN standard called "FEEL" for “Friendly Enough Expression Language”.
Data Type Guide
Operation
Expression |
Description |
Example |
+ |
Addition |
10+20 |
- |
Subtraction |
20-10 |
/ |
Division |
20/10 |
* |
Multiplication |
10*20 |
** |
To the power of |
10**3 means 10^3 |
Input test
Expression |
Description |
Example |
value |
Equals to value |
=4 means equals 4 |
>value |
Greater than value |
>10 |
>=value |
Greater or equals to value |
>=20 |
<value |
Smaller than value |
<10 |
⇐value |
Smaller or equals to value |
⇐20 |
[Value1..Value2] |
Close interval, between Value1 and Value2 inclusive |
[10..20] means >=10 and ⇐20 |
(Value1..Value2) |
Open interval, between Value1 and Value2 exclusive (ex.: (10..20) means >10 and <20) |
(10..20) means >10 and <20 |
[Value1..Value2) |
Interval, >=Value1 and <Value2 |
[10..20) means >=10 and <20 |
(Value1..Value2] |
Interval, >Value1 and ⇐Value2 |
(10..20] means >10 and ⇐20 |
not(value) |
Is not val. Works on all types |
not("Student") will be true if the input is anything but "Student". |
[Value1,Value2] |
Works as an "or". Works for numbers as well. |
["Student","Teacher"] means" Student" or "Teacher" |
A dash "-" symbol can represent any value.
FEEL Data Types
The types below can be combined with the expressions above to create advanced expression in the decision logic.
Days and Time Duration
Types |
Description |
Example |
duration("PnDTnHnMnS") |
Duration for days and time where "n" is a variable |
duration("P3DT4H17M32S") means duration of 3 days, 4 hours, 17 minutes and 32 seconds. |
Years and Months Duration
Types |
Description |
Example |
duration("PnYnM") |
Duration for years and months where "n" is a variable |
duration("P2Y7M") means duration of 2 years and 7 months. |
Date
Types |
Description |
Example |
date("YYYY-MM-DD") |
Date |
date("2016-02-08") means The 8th of February 2016. |
Time
Types |
Description |
Example |
time("HH:mm:ss") |
Time |
time("13:06:57") means 1PM, 6minutes and 57 seconds. |
Date and time
Types |
Description |
Example |
date and time("YYYY-MM-DD HH:mm:ss") |
Date and Time |
date and time("2016-02-08 13:06:57") means The 8th of February 2016 at 1PM, 6minutes and 57 seconds. |
Below is a concrete example for Vacation Days allocated to employees depending on their age and years of service:
