Singular

it seems that escaping quotes does not help when applying function construction from string iteratively:
we also have to escape backslashes:

[code]
LIB("findifs.lib");


proc foo ()
{
string bar = "sdfs";
return (0);
}
foo;

string fooStr = string(foo);
fooStr;


def fooStrMod = replace(fooStr,"\"","\\\"");

string cmd = "proc bar( )
{
proc rfoo=\""+fooStrMod+"\";
return (rfoo());
}";

cmd;
execute (cmd);

bar();


string barStr = string(bar);
barStr;



def barStrMod = replace(barStr,"\\","\\\\");

def barStrMod2 = replace(barStrMod,"\"","\\\"");

cmd = "proc foobar( )
{
proc rbar=\""+barStrMod2+"\";
return (rbar()+2);
}";

cmd;
execute (cmd);

foobar();

[/code]

does the principle of dump differ?

If this isn't gonna work in a generic way (without writing a parser for the Singular language),
the closest approach to compose generator functions without parameters from other functions
would be to introduce intermediate global functions (randomly named):

github.com/Singular/Sources/issues/558

Your problem can be solved by global search&replace of `"` with `\"` inside `fooStr` before you construct [i]cmd[/i]:

[code]
> string fooStr2 = string(fooStr[1..18]) + "\\" + string(fooStr[19..23]) + "\\" + string(fooStr[24..size(fooStr)]);
> fooStr2;


string bar = \"sdfs\";
return (0);


;return();

> string cmd = "proc bar( )
. { proc rfoo=\""+fooStr2 +"\"; return (rfoo());
. }"; cmd;

proc bar( )
{ proc rfoo="

string bar = \"sdfs\";
return (0);


;return();

"; return (rfoo());
}
> execute (cmd); bar();
0
[/code]


But since generating a procedure via execute can be very troublesome i would [b]not[/b] recommend any of such string manipulations in the Singular interpreter!

Hello,

I also would like to compose a command to define a function as below:
[code]
proc foo ()
{
string bar = "sdfs";
return (0);
}
foo;

string fooStr = string(foo);
fooStr;

string cmd = "proc bar( )
{
proc rfoo=\""+fooStr+"\";
return (rfoo());
}";

cmd;
execute (cmd);

bar();
[/code]
Now it is probably mandatory to escape 'fooStr';
How should this be done?

It should be possible:

[code]> proc a()
. { return (-666); };
> a();
-666
> string (a);

return (-666);

;return();
> proc A = string (a);
> A();
-666
[/code]

you can also take a look at [b]dump[/b] and [b]getdump[/b], which can store procedures in a text file...

Hello,


is it possible to reconstruct a function from a string?

[code]
proc foo( int param )
{
return(0);
}
string fooStr = string(foo);
fooStr;
// parameter int param ;
//
// return(0);
//
//
// ;return();
[/code]

if yes, is it reliable?

Thanks,

Jack