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Comp
Syntax
Comp(E:LIST, RECORD, STRING, or VECTOR,X_1:INT,...,X_k:INT):OBJECT
Summary
the N-th component of a list
Description
This function returns E[X_1,...,X_k] except in the case where there
are no additional arguments X_1,...,X_k, in which case E, itself, is
returned (in other words 'Comp(E)' returns E).

Example

Use R ::= Q[x,y,z];
L := [4,5,[6,7],8];
Comp(L,1);
4
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Comp(L,3);
[6, 7]
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Comp(L,3,2);
7
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F(X):=[X,X^2];  -- the following usage of 'Comp' is useful for
                -- programming 
F(2);
[2, 4]
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Comp(F(2),2);
4
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Struct := Record[L := [x,y,z], S := "string"];
Struct["L",3];       -- 'Comp' works for records also
z
-------------------------------
Comp(Struct,"L",3);
z
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Comp("this is a string",3);  -- use of 'Comp' with strings
i
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