How to write local function which can be called from different levels - KX Learning Hub

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How to write local function which can be called from different levels

Posted by vivo on July 29, 2022 at 12:00 am
Hi,

My code below works without error:

No Error
```
g:`;
g:{[xG] xG + 2}; // global; works for f and h
f:{[xF] 
h:{[xH] g[xH] + 3};
show g[xF] + h[xF];
}
f[40]; // i.e. 87; no error
```
However, I prefer a local g instead of a local one. I also tried below, but both failed:

Trial 1 (Failed)
```
g:`;
f:{[xF] 
g:{[xG] xG + 2}; // local; doesn't work for h
h:{[xH] g[xH] + 3};
show g[xF] + h[xF];
}
f[40]; // error
```
and

Trial 2 (Failed)
```
g:`;
f:{[xF] 
h:{[xH] g:{[xG] xG + 2}; g[xH] + 3}; // local; doesn't work for f
show g[xF] + h[xF];
}
f[40];// error
```
Is it possible to have a local g without an error? Thanks.
vivo replied 9 months, 1 week ago 2 Members · 1 Reply
1 Reply

rocuinneagain

Member

July 29, 2022 at 12:00 am

You could pass it in to a projection

q)f:{[xF] g:{[xG] xG + 2};
       h:{[g;xH] g[xH] + 3}[g];
       g[xF] + h[xF]} 
q)f[40] 
87

Or composition in this basic case

q)f:{[xF] g:{[xG] xG + 2};
        h:+[3] g @;
        g[xF] + h[xF]} 
q)f[40] 
87

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