In the IDC expressions you can use almost all C operations except:
Index
| Previous topic
| Next topic
complex assignment operations as '+='Constants are defined more or less like in C, with some minor differences.
There are four type conversion operations:
long(expr) floating point numbers are truncated during conversion char(expr) float(expr) __int64(expr)However, explicit type conversions are rarely required because all type conversions are made automatically:
- addition: if both operands are strings, string addition is performed (strings are concatenated); if both operands are objects, object combination is performed (a new object is created) if floating point operand exists, both operands are converted to floats; otherwise both operands are converted to longs;
- subtraction/multiplication/division: if floating point operand exists, both operands are converted to floats; if both operands are objects and the operation is subtraction, object subtraction is performed (a new object is created) otherwise both operands are converted to longs;
- comparisons (==,!=, etc): if both operands are strings, string comparison is performed; if floating point operand exists, both operands are converted to floats; otherwise both operands are converted to numbers;
- all other operations: operand(s) are converted to longs;If any of the long operands is 64bit, the other operand is converted to 64bit too.
There is one notable exception concerning type conversions: if one operand is a string and the other is zero (0), then a string operation is performed. Zero is converted to an empty string in this case.
The & operator is used to take a reference to a variable. References themselves cannot be modified once created. Any assignment to them will modify the target variable. For example:
auto x, r; r = &x; r = 1; // x is equal to 1 nowReferences to references are immediately resolved:
auto x, r1, r2; r1 = &x; r2 = &r1; // r2 points to xSince all non-object arguments are passed to functions by value, references are a good way to pass arguments by reference.