Functions and description of lines

Binome · Feb 21, 2017

Hi,
I've downloaded a project with a testbench where LINE type is used.
I read

Code:

variable line_in : line

then

Code:

if(line_in(1)='.') then...

I don't understand this handling very well. The line_in object is a pointer to a characters string, right? Then line_in(1) means the first character?
I'd like a precise description of that.

srizbf · Feb 21, 2017

using the
USE std.textio.ALL;
for text related operations,

variable line_in:line;
makes the text buffer line_in of 'line' type

and line_in(1) points to the specified character in the buffer.

TrickyDicky · Feb 21, 2017

Binome said:
Hi,
I've downloaded a project with a testbench where LINE type is used.
I read

Code:

variable line_in : line

then

Code:

if(line_in(1)='.') then...

I don't understand this handling very well. The line_in object is a pointer to a characters string, right? Then line_in(1) means the first character?
I'd like a precise description of that.

Yes, you are correct. But be aware that because it's a pointer then line_in(1) may not exist and you'll get a bad pointer reference error during runtime.
For example:
Accessing a line thats been used already in writeline, as writeline deallocations the pointer
Accessing a line that hasnt been created from a readline
Createing the pointer manually, that doesnt have index 1:

line_in := new string(2 to 10);

Functions and description of lines

Binome

Full Member level 3

srizbf

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TrickyDicky

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Functions and description of lines

Binome

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