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Does C++20 mandate source code being stored in files?
Is it possible to get gcc to read from a pipe?How to make GCC output to stdout?Storing C++ template function definitions in a .CPP fileC++ code file extension? .cc vs .cppUsing Unicode in a C++ source fileDoes the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor implementation?How do I achieve the theoretical maximum of 4 FLOPs per cycle?Why does GCC generate 15-20% faster code if I optimize for size instead of speed?Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviationsDoes C++20 well-define left shift for signed integers that “overflow”?
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A slightly strange question, however, if I remember correctly , c++ source code doesn't require a file system to store it's files.
Having a compiler that scans handwritten papers via a camera would be a conforming implementation. Although practically not making that much sense.
However c++20 now adds source_location with file_name. Does this now imply that source code should always be stored in a file?
c++ language-lawyer c++20 std-source-location
edited 8 hours ago
einpoklum
42.3k28 gold badges147 silver badges292 bronze badges
asked 8 hours ago
JVApenJVApen
6,6661 gold badge15 silver badges45 bronze badges
|
show 1 more comment
A slightly strange question, however, if I remember correctly , c++ source code doesn't require a file system to store it's files.
Having a compiler that scans handwritten papers via a camera would be a conforming implementation. Although practically not making that much sense.
However c++20 now adds source_location with file_name. Does this now imply that source code should always be stored in a file?
c++ language-lawyer c++20 std-source-location
edited 8 hours ago
einpoklum
42.3k28 gold badges147 silver badges292 bronze badges
asked 8 hours ago
JVApenJVApen
6,6661 gold badge15 silver badges45 bronze badges
1
This has been in C since forever -__FILE__. Classsource_locationjust allows you to get it at function call site.
– StaceyGirl
8 hours ago
Can't you give filename to your handwritten papers?
– Jarod42
8 hours ago
3
I think it is an implementation detail whether the source code is in files, or something else. If the compiler can be fed source code through stdin, the source could be in a database.
– Eljay
8 hours ago
2
My example may be a bit off, but if you use some on-the-fly compiler, such as TCC you can always supply some human readable source name for the sake of error reporting even though you compile directly from memory. That is having a "file name" does not imply being stored as a file at all.
– VTT
8 hours ago
2
Surely it's the implementation files such as<iostream>that may not be files (if you see what I mean), not the files written by developers?
– Neil Butterworth
8 hours ago
|
show 1 more comment
A slightly strange question, however, if I remember correctly , c++ source code doesn't require a file system to store it's files.
Having a compiler that scans handwritten papers via a camera would be a conforming implementation. Although practically not making that much sense.
However c++20 now adds source_location with file_name. Does this now imply that source code should always be stored in a file?
c++ language-lawyer c++20 std-source-location
edited 8 hours ago
einpoklum
42.3k28 gold badges147 silver badges292 bronze badges
asked 8 hours ago
JVApenJVApen
6,6661 gold badge15 silver badges45 bronze badges
A slightly strange question, however, if I remember correctly , c++ source code doesn't require a file system to store it's files.
Having a compiler that scans handwritten papers via a camera would be a conforming implementation. Although practically not making that much sense.
However c++20 now adds source_location with file_name. Does this now imply that source code should always be stored in a file?
c++ language-lawyer c++20 std-source-location
c++ language-lawyer c++20 std-source-location
edited 8 hours ago
einpoklum
42.3k28 gold badges147 silver badges292 bronze badges
asked 8 hours ago
JVApenJVApen
6,6661 gold badge15 silver badges45 bronze badges
edited 8 hours ago
einpoklum
42.3k28 gold badges147 silver badges292 bronze badges
asked 8 hours ago
JVApenJVApen
6,6661 gold badge15 silver badges45 bronze badges
edited 8 hours ago
einpoklum
42.3k28 gold badges147 silver badges292 bronze badges
edited 8 hours ago
einpoklum
42.3k28 gold badges147 silver badges292 bronze badges
edited 8 hours ago
einpoklum
42.3k28 gold badges147 silver badges292 bronze badges
42.3k28 gold badges147 silver badges292 bronze badges
asked 8 hours ago
JVApenJVApen
6,6661 gold badge15 silver badges45 bronze badges
asked 8 hours ago
JVApenJVApen
6,6661 gold badge15 silver badges45 bronze badges
asked 8 hours ago
JVApenJVApen
6,6661 gold badge15 silver badges45 bronze badges
6,6661 gold badge15 silver badges45 bronze badges
1
This has been in C since forever -__FILE__. Classsource_locationjust allows you to get it at function call site.
– StaceyGirl
8 hours ago
Can't you give filename to your handwritten papers?
– Jarod42
8 hours ago
3
I think it is an implementation detail whether the source code is in files, or something else. If the compiler can be fed source code through stdin, the source could be in a database.
– Eljay
8 hours ago
2
My example may be a bit off, but if you use some on-the-fly compiler, such as TCC you can always supply some human readable source name for the sake of error reporting even though you compile directly from memory. That is having a "file name" does not imply being stored as a file at all.
– VTT
8 hours ago
2
Surely it's the implementation files such as<iostream>that may not be files (if you see what I mean), not the files written by developers?
– Neil Butterworth
8 hours ago
|
show 1 more comment
1
This has been in C since forever -__FILE__. Classsource_locationjust allows you to get it at function call site.
– StaceyGirl
8 hours ago
Can't you give filename to your handwritten papers?
– Jarod42
8 hours ago
3
I think it is an implementation detail whether the source code is in files, or something else. If the compiler can be fed source code through stdin, the source could be in a database.
– Eljay
8 hours ago
2
My example may be a bit off, but if you use some on-the-fly compiler, such as TCC you can always supply some human readable source name for the sake of error reporting even though you compile directly from memory. That is having a "file name" does not imply being stored as a file at all.
– VTT
8 hours ago
2
Surely it's the implementation files such as<iostream>that may not be files (if you see what I mean), not the files written by developers?
– Neil Butterworth
8 hours ago
1
1
This has been in C since forever -
__FILE__. Class source_location just allows you to get it at function call site.– StaceyGirl
8 hours ago
This has been in C since forever -
__FILE__. Class source_location just allows you to get it at function call site.– StaceyGirl
8 hours ago
Can't you give filename to your handwritten papers?
– Jarod42
8 hours ago
Can't you give filename to your handwritten papers?
– Jarod42
8 hours ago
3
3
I think it is an implementation detail whether the source code is in files, or something else. If the compiler can be fed source code through stdin, the source could be in a database.
– Eljay
8 hours ago
I think it is an implementation detail whether the source code is in files, or something else. If the compiler can be fed source code through stdin, the source could be in a database.
– Eljay
8 hours ago
2
2
My example may be a bit off, but if you use some on-the-fly compiler, such as TCC you can always supply some human readable source name for the sake of error reporting even though you compile directly from memory. That is having a "file name" does not imply being stored as a file at all.
– VTT
8 hours ago
My example may be a bit off, but if you use some on-the-fly compiler, such as TCC you can always supply some human readable source name for the sake of error reporting even though you compile directly from memory. That is having a "file name" does not imply being stored as a file at all.
– VTT
8 hours ago
2
2
Surely it's the implementation files such as
<iostream> that may not be files (if you see what I mean), not the files written by developers?– Neil Butterworth
8 hours ago
Surely it's the implementation files such as
<iostream> that may not be files (if you see what I mean), not the files written by developers?– Neil Butterworth
8 hours ago
|
show 1 more comment
2 Answers
2
active
oldest
votes
Even before c++20, the standard has had:
__FILE__
The presumed name of the current source file (a character string literal).
The definition is same for source_location::file_name.
As such, there has not been a change in regard to support for filesystemless implementations in c++20.
The standard doesn't exactly define what "source file" means, so whether it refers to a file system may be up to interpretation. Presumably, it could be conforming for an implementation to produce "the handwritten note that you gave to me just then" if that indeed identifies the "source file" in that implementation of the language.
In conclusion: Yeah, sources are referred to as "files" by the standard, but what a "file" is and whether a file system is involved is unspecified.
answered 8 hours ago
eerorikaeerorika
103k6 gold badges82 silver badges157 bronze badges
What does "presumed" mean in this context? Can there be an ambiguity?
– Yksisarvinen
8 hours ago
2
#linecan update the name
– JVApen
8 hours ago
I'm wondering, does my initial claim (not stored in file) contain a mistake, or is there a behavior for that case?
– JVApen
8 hours ago
1
@Yksisarvinen I don't know exactly the intention of the "presumption" qualification of the rule, but I presume :) that it is an clarification that the file name doest need to be absolute or canonical, but rather a relative name from perspective of the compiler is sufficient. I could be wrong.
– eerorika
8 hours ago
add a comment |
No, source code doesn't have to come from a file.
Yo can compile C++ completely within a pipe, putting your compiler in the middle, e.g.
generate_source | g++ -o- -xc++ - | do_something_with_the_binary
(See also:
- Is it possible to get gcc to read from a pipe?
- How to make GCC output to stdout?
) and the introduction of std::source_location in C++20 doesn't change that. It's just that some code will not have a well-defined source location. Actually, I'd say that the insistence on defining source_location using files is somewhat short-sighted or myopic... although in fairness, it's just a macro-less equivalent of __FILE__ and __LINE__ which already exist in C++ (and C), and have for decades.
Are you a language lawyer? Ok, so let's consult the standard..
The question of whether C++ program sources need to come from files is not answered clearly in the language standard. Looking at a draft of the C++17 standard (n4713), section 5.1 [lex.separate] reads:
- The text of the program is kept in units called source files in this document. A source file together with all the headers (20.5.1.2) and source files included (19.2) via the preprocessing directive #include, less any source lines skipped by any of the conditional inclusion (19.1) preprocessing directives, is called a translation unit.
So, the source code is not necessarily kept in a file per se, but in a "unit called a file". But then, where do the includes come from? One would assume they come from files... but that to is not mandated.
At any rate, std::source_location does not seem to change that in C++20 (AFAICT).
answered 7 hours ago
einpoklumeinpoklum
42.3k28 gold badges147 silver badges292 bronze badges
2
That pipe is a "source file" for the purposes of the standard.
– melpomene
7 hours ago
@melpomene: 1. Reference please. 2. But it's not a bona fide file...
– einpoklum
7 hours ago
2
I'm looking at the C standard, which defines: "The text of the program is kept in units called source files, (or preprocessing files) in this International Standard." So wherever the code is stored, that's a "source file" in Standardese. (Addendum: Similar language is found in the C++ standard under [lex].)
– melpomene
7 hours ago
1
@melpomene: The units are just called source files, it doesn't say that they actually have to be source files. But I'll edit the answer to include this.
– einpoklum
7 hours ago
add a comment |
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Even before c++20, the standard has had:
__FILE__
The presumed name of the current source file (a character string literal).
The definition is same for source_location::file_name.
As such, there has not been a change in regard to support for filesystemless implementations in c++20.
The standard doesn't exactly define what "source file" means, so whether it refers to a file system may be up to interpretation. Presumably, it could be conforming for an implementation to produce "the handwritten note that you gave to me just then" if that indeed identifies the "source file" in that implementation of the language.
In conclusion: Yeah, sources are referred to as "files" by the standard, but what a "file" is and whether a file system is involved is unspecified.
answered 8 hours ago
eerorikaeerorika
103k6 gold badges82 silver badges157 bronze badges
What does "presumed" mean in this context? Can there be an ambiguity?
– Yksisarvinen
8 hours ago
2
#linecan update the name
– JVApen
8 hours ago
I'm wondering, does my initial claim (not stored in file) contain a mistake, or is there a behavior for that case?
– JVApen
8 hours ago
1
@Yksisarvinen I don't know exactly the intention of the "presumption" qualification of the rule, but I presume :) that it is an clarification that the file name doest need to be absolute or canonical, but rather a relative name from perspective of the compiler is sufficient. I could be wrong.
– eerorika
8 hours ago
add a comment |
Even before c++20, the standard has had:
__FILE__
The presumed name of the current source file (a character string literal).
The definition is same for source_location::file_name.
As such, there has not been a change in regard to support for filesystemless implementations in c++20.
The standard doesn't exactly define what "source file" means, so whether it refers to a file system may be up to interpretation. Presumably, it could be conforming for an implementation to produce "the handwritten note that you gave to me just then" if that indeed identifies the "source file" in that implementation of the language.
In conclusion: Yeah, sources are referred to as "files" by the standard, but what a "file" is and whether a file system is involved is unspecified.
answered 8 hours ago
eerorikaeerorika
103k6 gold badges82 silver badges157 bronze badges
What does "presumed" mean in this context? Can there be an ambiguity?
– Yksisarvinen
8 hours ago
2
#linecan update the name
– JVApen
8 hours ago
I'm wondering, does my initial claim (not stored in file) contain a mistake, or is there a behavior for that case?
– JVApen
8 hours ago
1
@Yksisarvinen I don't know exactly the intention of the "presumption" qualification of the rule, but I presume :) that it is an clarification that the file name doest need to be absolute or canonical, but rather a relative name from perspective of the compiler is sufficient. I could be wrong.
– eerorika
8 hours ago
add a comment |
Even before c++20, the standard has had:
__FILE__
The presumed name of the current source file (a character string literal).
The definition is same for source_location::file_name.
As such, there has not been a change in regard to support for filesystemless implementations in c++20.
The standard doesn't exactly define what "source file" means, so whether it refers to a file system may be up to interpretation. Presumably, it could be conforming for an implementation to produce "the handwritten note that you gave to me just then" if that indeed identifies the "source file" in that implementation of the language.
In conclusion: Yeah, sources are referred to as "files" by the standard, but what a "file" is and whether a file system is involved is unspecified.
answered 8 hours ago
eerorikaeerorika
103k6 gold badges82 silver badges157 bronze badges
Even before c++20, the standard has had:
__FILE__
The presumed name of the current source file (a character string literal).
The definition is same for source_location::file_name.
As such, there has not been a change in regard to support for filesystemless implementations in c++20.
The standard doesn't exactly define what "source file" means, so whether it refers to a file system may be up to interpretation. Presumably, it could be conforming for an implementation to produce "the handwritten note that you gave to me just then" if that indeed identifies the "source file" in that implementation of the language.
In conclusion: Yeah, sources are referred to as "files" by the standard, but what a "file" is and whether a file system is involved is unspecified.
answered 8 hours ago
eerorikaeerorika
103k6 gold badges82 silver badges157 bronze badges
edited 8 hours ago
answered 8 hours ago
eerorikaeerorika
103k6 gold badges82 silver badges157 bronze badges
answered 8 hours ago
eerorikaeerorika
103k6 gold badges82 silver badges157 bronze badges
answered 8 hours ago
eerorikaeerorika
103k6 gold badges82 silver badges157 bronze badges
103k6 gold badges82 silver badges157 bronze badges
What does "presumed" mean in this context? Can there be an ambiguity?
– Yksisarvinen
8 hours ago
2
#linecan update the name
– JVApen
8 hours ago
I'm wondering, does my initial claim (not stored in file) contain a mistake, or is there a behavior for that case?
– JVApen
8 hours ago
1
@Yksisarvinen I don't know exactly the intention of the "presumption" qualification of the rule, but I presume :) that it is an clarification that the file name doest need to be absolute or canonical, but rather a relative name from perspective of the compiler is sufficient. I could be wrong.
– eerorika
8 hours ago
add a comment |
What does "presumed" mean in this context? Can there be an ambiguity?
– Yksisarvinen
8 hours ago
2
#linecan update the name
– JVApen
8 hours ago
I'm wondering, does my initial claim (not stored in file) contain a mistake, or is there a behavior for that case?
– JVApen
8 hours ago
1
@Yksisarvinen I don't know exactly the intention of the "presumption" qualification of the rule, but I presume :) that it is an clarification that the file name doest need to be absolute or canonical, but rather a relative name from perspective of the compiler is sufficient. I could be wrong.
– eerorika
8 hours ago
What does "presumed" mean in this context? Can there be an ambiguity?
– Yksisarvinen
8 hours ago
What does "presumed" mean in this context? Can there be an ambiguity?
– Yksisarvinen
8 hours ago
2
2
#line can update the name– JVApen
8 hours ago
#line can update the name– JVApen
8 hours ago
I'm wondering, does my initial claim (not stored in file) contain a mistake, or is there a behavior for that case?
– JVApen
8 hours ago
I'm wondering, does my initial claim (not stored in file) contain a mistake, or is there a behavior for that case?
– JVApen
8 hours ago
1
1
@Yksisarvinen I don't know exactly the intention of the "presumption" qualification of the rule, but I presume :) that it is an clarification that the file name doest need to be absolute or canonical, but rather a relative name from perspective of the compiler is sufficient. I could be wrong.
– eerorika
8 hours ago
@Yksisarvinen I don't know exactly the intention of the "presumption" qualification of the rule, but I presume :) that it is an clarification that the file name doest need to be absolute or canonical, but rather a relative name from perspective of the compiler is sufficient. I could be wrong.
– eerorika
8 hours ago
add a comment |
No, source code doesn't have to come from a file.
Yo can compile C++ completely within a pipe, putting your compiler in the middle, e.g.
generate_source | g++ -o- -xc++ - | do_something_with_the_binary
(See also:
- Is it possible to get gcc to read from a pipe?
- How to make GCC output to stdout?
) and the introduction of std::source_location in C++20 doesn't change that. It's just that some code will not have a well-defined source location. Actually, I'd say that the insistence on defining source_location using files is somewhat short-sighted or myopic... although in fairness, it's just a macro-less equivalent of __FILE__ and __LINE__ which already exist in C++ (and C), and have for decades.
Are you a language lawyer? Ok, so let's consult the standard..
The question of whether C++ program sources need to come from files is not answered clearly in the language standard. Looking at a draft of the C++17 standard (n4713), section 5.1 [lex.separate] reads:
- The text of the program is kept in units called source files in this document. A source file together with all the headers (20.5.1.2) and source files included (19.2) via the preprocessing directive #include, less any source lines skipped by any of the conditional inclusion (19.1) preprocessing directives, is called a translation unit.
So, the source code is not necessarily kept in a file per se, but in a "unit called a file". But then, where do the includes come from? One would assume they come from files... but that to is not mandated.
At any rate, std::source_location does not seem to change that in C++20 (AFAICT).
answered 7 hours ago
einpoklumeinpoklum
42.3k28 gold badges147 silver badges292 bronze badges
2
That pipe is a "source file" for the purposes of the standard.
– melpomene
7 hours ago
@melpomene: 1. Reference please. 2. But it's not a bona fide file...
– einpoklum
7 hours ago
2
I'm looking at the C standard, which defines: "The text of the program is kept in units called source files, (or preprocessing files) in this International Standard." So wherever the code is stored, that's a "source file" in Standardese. (Addendum: Similar language is found in the C++ standard under [lex].)
– melpomene
7 hours ago
1
@melpomene: The units are just called source files, it doesn't say that they actually have to be source files. But I'll edit the answer to include this.
– einpoklum
7 hours ago
add a comment |
No, source code doesn't have to come from a file.
Yo can compile C++ completely within a pipe, putting your compiler in the middle, e.g.
generate_source | g++ -o- -xc++ - | do_something_with_the_binary
(See also:
- Is it possible to get gcc to read from a pipe?
- How to make GCC output to stdout?
) and the introduction of std::source_location in C++20 doesn't change that. It's just that some code will not have a well-defined source location. Actually, I'd say that the insistence on defining source_location using files is somewhat short-sighted or myopic... although in fairness, it's just a macro-less equivalent of __FILE__ and __LINE__ which already exist in C++ (and C), and have for decades.
Are you a language lawyer? Ok, so let's consult the standard..
The question of whether C++ program sources need to come from files is not answered clearly in the language standard. Looking at a draft of the C++17 standard (n4713), section 5.1 [lex.separate] reads:
- The text of the program is kept in units called source files in this document. A source file together with all the headers (20.5.1.2) and source files included (19.2) via the preprocessing directive #include, less any source lines skipped by any of the conditional inclusion (19.1) preprocessing directives, is called a translation unit.
So, the source code is not necessarily kept in a file per se, but in a "unit called a file". But then, where do the includes come from? One would assume they come from files... but that to is not mandated.
At any rate, std::source_location does not seem to change that in C++20 (AFAICT).
answered 7 hours ago
einpoklumeinpoklum
42.3k28 gold badges147 silver badges292 bronze badges
2
That pipe is a "source file" for the purposes of the standard.
– melpomene
7 hours ago
@melpomene: 1. Reference please. 2. But it's not a bona fide file...
– einpoklum
7 hours ago
2
I'm looking at the C standard, which defines: "The text of the program is kept in units called source files, (or preprocessing files) in this International Standard." So wherever the code is stored, that's a "source file" in Standardese. (Addendum: Similar language is found in the C++ standard under [lex].)
– melpomene
7 hours ago
1
@melpomene: The units are just called source files, it doesn't say that they actually have to be source files. But I'll edit the answer to include this.
– einpoklum
7 hours ago
add a comment |
No, source code doesn't have to come from a file.
Yo can compile C++ completely within a pipe, putting your compiler in the middle, e.g.
generate_source | g++ -o- -xc++ - | do_something_with_the_binary
(See also:
- Is it possible to get gcc to read from a pipe?
- How to make GCC output to stdout?
) and the introduction of std::source_location in C++20 doesn't change that. It's just that some code will not have a well-defined source location. Actually, I'd say that the insistence on defining source_location using files is somewhat short-sighted or myopic... although in fairness, it's just a macro-less equivalent of __FILE__ and __LINE__ which already exist in C++ (and C), and have for decades.
Are you a language lawyer? Ok, so let's consult the standard..
The question of whether C++ program sources need to come from files is not answered clearly in the language standard. Looking at a draft of the C++17 standard (n4713), section 5.1 [lex.separate] reads:
- The text of the program is kept in units called source files in this document. A source file together with all the headers (20.5.1.2) and source files included (19.2) via the preprocessing directive #include, less any source lines skipped by any of the conditional inclusion (19.1) preprocessing directives, is called a translation unit.
So, the source code is not necessarily kept in a file per se, but in a "unit called a file". But then, where do the includes come from? One would assume they come from files... but that to is not mandated.
At any rate, std::source_location does not seem to change that in C++20 (AFAICT).
answered 7 hours ago
einpoklumeinpoklum
42.3k28 gold badges147 silver badges292 bronze badges
No, source code doesn't have to come from a file.
Yo can compile C++ completely within a pipe, putting your compiler in the middle, e.g.
generate_source | g++ -o- -xc++ - | do_something_with_the_binary
(See also:
- Is it possible to get gcc to read from a pipe?
- How to make GCC output to stdout?
) and the introduction of std::source_location in C++20 doesn't change that. It's just that some code will not have a well-defined source location. Actually, I'd say that the insistence on defining source_location using files is somewhat short-sighted or myopic... although in fairness, it's just a macro-less equivalent of __FILE__ and __LINE__ which already exist in C++ (and C), and have for decades.
Are you a language lawyer? Ok, so let's consult the standard..
The question of whether C++ program sources need to come from files is not answered clearly in the language standard. Looking at a draft of the C++17 standard (n4713), section 5.1 [lex.separate] reads:
- The text of the program is kept in units called source files in this document. A source file together with all the headers (20.5.1.2) and source files included (19.2) via the preprocessing directive #include, less any source lines skipped by any of the conditional inclusion (19.1) preprocessing directives, is called a translation unit.
So, the source code is not necessarily kept in a file per se, but in a "unit called a file". But then, where do the includes come from? One would assume they come from files... but that to is not mandated.
At any rate, std::source_location does not seem to change that in C++20 (AFAICT).
answered 7 hours ago
einpoklumeinpoklum
42.3k28 gold badges147 silver badges292 bronze badges
edited 7 hours ago
answered 7 hours ago
einpoklumeinpoklum
42.3k28 gold badges147 silver badges292 bronze badges
answered 7 hours ago
einpoklumeinpoklum
42.3k28 gold badges147 silver badges292 bronze badges
answered 7 hours ago
einpoklumeinpoklum
42.3k28 gold badges147 silver badges292 bronze badges
42.3k28 gold badges147 silver badges292 bronze badges
2
That pipe is a "source file" for the purposes of the standard.
– melpomene
7 hours ago
@melpomene: 1. Reference please. 2. But it's not a bona fide file...
– einpoklum
7 hours ago
2
I'm looking at the C standard, which defines: "The text of the program is kept in units called source files, (or preprocessing files) in this International Standard." So wherever the code is stored, that's a "source file" in Standardese. (Addendum: Similar language is found in the C++ standard under [lex].)
– melpomene
7 hours ago
1
@melpomene: The units are just called source files, it doesn't say that they actually have to be source files. But I'll edit the answer to include this.
– einpoklum
7 hours ago
add a comment |
2
That pipe is a "source file" for the purposes of the standard.
– melpomene
7 hours ago
@melpomene: 1. Reference please. 2. But it's not a bona fide file...
– einpoklum
7 hours ago
2
I'm looking at the C standard, which defines: "The text of the program is kept in units called source files, (or preprocessing files) in this International Standard." So wherever the code is stored, that's a "source file" in Standardese. (Addendum: Similar language is found in the C++ standard under [lex].)
– melpomene
7 hours ago
1
@melpomene: The units are just called source files, it doesn't say that they actually have to be source files. But I'll edit the answer to include this.
– einpoklum
7 hours ago
2
2
That pipe is a "source file" for the purposes of the standard.
– melpomene
7 hours ago
That pipe is a "source file" for the purposes of the standard.
– melpomene
7 hours ago
@melpomene: 1. Reference please. 2. But it's not a bona fide file...
– einpoklum
7 hours ago
@melpomene: 1. Reference please. 2. But it's not a bona fide file...
– einpoklum
7 hours ago
2
2
I'm looking at the C standard, which defines: "The text of the program is kept in units called source files, (or preprocessing files) in this International Standard." So wherever the code is stored, that's a "source file" in Standardese. (Addendum: Similar language is found in the C++ standard under [lex].)
– melpomene
7 hours ago
I'm looking at the C standard, which defines: "The text of the program is kept in units called source files, (or preprocessing files) in this International Standard." So wherever the code is stored, that's a "source file" in Standardese. (Addendum: Similar language is found in the C++ standard under [lex].)
– melpomene
7 hours ago
1
1
@melpomene: The units are just called source files, it doesn't say that they actually have to be source files. But I'll edit the answer to include this.
– einpoklum
7 hours ago
@melpomene: The units are just called source files, it doesn't say that they actually have to be source files. But I'll edit the answer to include this.
– einpoklum
7 hours ago
add a comment |
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1
This has been in C since forever -
__FILE__. Classsource_locationjust allows you to get it at function call site.– StaceyGirl
8 hours ago
Can't you give filename to your handwritten papers?
– Jarod42
8 hours ago
3
I think it is an implementation detail whether the source code is in files, or something else. If the compiler can be fed source code through stdin, the source could be in a database.
– Eljay
8 hours ago
2
My example may be a bit off, but if you use some on-the-fly compiler, such as TCC you can always supply some human readable source name for the sake of error reporting even though you compile directly from memory. That is having a "file name" does not imply being stored as a file at all.
– VTT
8 hours ago
2
Surely it's the implementation files such as
<iostream>that may not be files (if you see what I mean), not the files written by developers?– Neil Butterworth
8 hours ago