diff options
| -rw-r--r-- | subx/000organization.cc | 7 | ||||
| -rw-r--r-- | subx/001help.cc | 55 |
2 files changed, 53 insertions, 9 deletions
diff --git a/subx/000organization.cc b/subx/000organization.cc index 71acb491..a82fd67d 100644 --- a/subx/000organization.cc +++ b/subx/000organization.cc @@ -135,6 +135,13 @@ int main(int argc, char* argv[]) { //: Without directives or with the :(code) directive, lines get added at the //: end. +//: +//: Regardless of where functions are defined, we can call them anywhere we +//: like as long as we format the function header in a specific way: put it +//: all on a single line without indent, end the line with ') {' and no +//: trailing whitespace. As long as functions uniformly start this way, our +//: 'build' script contains a little command to automatically generate +//: declarations for them. :(code) void reset() { // End Reset diff --git a/subx/001help.cc b/subx/001help.cc index c4cc3a00..3b60f60f 100644 --- a/subx/001help.cc +++ b/subx/001help.cc @@ -10,19 +10,56 @@ if (argc <= 1 || is_equal(argv[1], "--help")) { << " subx --help\n" << " subx run <ELF binary>\n" << " subx translate <input 'source' file> <output ELF binary>\n" + << "\n" + << "To start learning how to write SubX programs, run:\n" + << " subx help\n" ; return 0; } -//:: Helper function used by the above fragment of code (and later layers too, -//:: who knows?). -//: The :(code) directive appends function definitions to the end of the -//: project. Regardless of where functions are defined, we can call them -//: anywhere we like as long as we format the function header in a specific -//: way: put it all on a single line without indent, end the line with ') {' -//: and no trailing whitespace. As long as functions uniformly start this -//: way, our 'build' script contains a little command to automatically -//: generate declarations for them. +if (is_equal(argv[1], "help")) { + if (argc == 2) { + cerr << "help on what?\n"; + help_contents(); + return 0; + } + else if (contains_key(Help, argv[2])) { + cerr << get(Help, argv[2]); + return 0; + } + else { + cerr << "No help found for '" << argv[2] << "'\n"; + help_contents(); + cerr << "Please check your command for typos.\n"; + return 1; + } +} + +:(code) +void help_contents() { + cerr << "Available top-level topics:\n"; + cerr << " syntax\n"; + // End Help Contents +} + +:(before "End Globals") +map<string, string> Help; +:(before "End One-time Setup") +init_help(); +:(code) +void init_help() { + put(Help, "syntax", + "SubX programs consist of segments, each segment in turn consisting of lines.\n" + "Line-endings are significant; each line should contain a single instruction, macro or directive.\n" + "Comments start with the '#' character. It should be at the start of a word (start of line, or following a space).\n" + "Each segment starts with a header line: a '--' delimiter followed by the starting address for the segment.\n" + "The starting address for a segment has some finicky requirements. But just start with a round number, and `subx` will try to guide you to the right answer.\n" + "Currently only the first segment contains executable code (because it gets annoying to have to change addresses in later segments every time an earlier one changes length).\n" + "Programming in machine code can be annoying, but let's see if we can make it nice enough to be able to write a compiler in it.\n" + ); + // End Help Texts +} + :(code) bool is_equal(char* s, const char* lit) { return strncmp(s, lit, strlen(lit)) == 0; |