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PrependTo

PrependTo(s, item)

prepend item to value of s and sets s to the result.

Examples

Assign s to a list

>> s = {1, 2, 4, 9}    
{1,2,4,9}   

Add a new value at the beginning of the list:

>> PrependTo(s, 0)    
{0,1,2,4,9}   

The value assigned to s has changed:

>> s    
{0,1,2,4,9}

PrependTo works with a head other than List:

>> y = f(a, b, c)    
>> PrependTo(y, x)    
f(x,a,b,c)  
 
>> y    
f(x,a,b,c) 

{a, b} is not a variable with a value, so its value cannot be changed.

>> PrependTo({a, b}, 1)    
PrependTo({a,b},1)   

a is not a variable with a value, so its value cannot be changed.

>> PrependTo(a, b)     
PrependTo(a,b)

>> x = 1 + 2    
3

Nonatomic expression expected at position 1 in PrependTo

>> PrependTo(x, {3, 4})      
PrependTo(x,{3,4})    

Implementation status

  • ✅ - full supported

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