lgwam(1) - f29

1LGWAM(1)                         User Commands                        LGWAM(1)
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NAME

6       lgwam - Logiweb Abstract Machine
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SYNOPSIS

9       lgwam command [file arg1 ...  argn]
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DESCRIPTION

12       In  normal use, the lgwam command is installed in /usr/bin/lgwam and is
13       used as the first line of Logiweb  scripts.  The  first  line  of  such
14       scripts typically read
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16           #!/usr/bin/lgwam script
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18       The  Logiweb  compiler  lgc(1)  generates  such  scripts. The format of
19       scripts is described in SCRIPT FORMAT below.
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OPTIONS

22       The lgwam command may take the following forms:
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24       lgwam script FILE ARG1 ... ARGn
25              Execute the given file as a Logiweb program.  Pass  the  command
26              line  arguments to the program with FILE as ARG0. For the format
27              of FILE see SCRIPT FORMAT below.
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29       lgwam execute FCT ARG1 ... ARGn
30              Same as above, but execute the given function. The function must
31              be  defined  on a page which has been compiled into lgwam. As an
32              example, if the lgc compiler has been compiled in,  then  'lgwam
33              execute  lgc  ARG1 ... ARGn' executes the lgc compiler but needs
34              no script file.
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36       lgwam test
37              Execute basic built in testsuite.
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39       lgwam testrun FILE
40              Load the Logiweb page referenced in FILE and  all  pages  refer‐
41              enced  transitively  from  that  page.  Then execute an extended
42              testsuite. The extended testsuite first executes the basic test‐
43              suite. Then the extended testsuite looks for pages named 'base',
44              'check', 'Peano', and 'test'. If one or more of these are found,
45              the  extended  testsuite  executes a number of associated tests.
46              The FILE must be a Logiweb script, c.f. SCRIPT FORMAT below.
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48       lgwam dry
49              Do dry run: initialize memory and exit.
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51       lgwam deff SOURCE OUT1 ... OUTn
52              Execute the deff-lisp program defined in SOURCE  and  write  the
53              output to the given output files. This option works even when no
54              pages have been compiled into lgwam. It is used  for  bootstrap‐
55              ping  the  system  in  that it allows to compile an lgc compiler
56              expressed in deff-lisp. That lgc compiler can then  be  used  to
57              compile an lgc compiler expressed in the compilers own language.
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59       lgwam { -h | help | --help }
60              Print help message
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62       lgwam { -v | version | --version }
63              Print version and license information.
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65       lgwam { pages | --pages }
66              List built in pages.
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SCRIPT FORMAT

69       A  Logiweb script file consists of lines of text. Blank lines and lines
70       starting with a hash mark (#) are ignored. Lines can be ended by  arbi‐
71       trary sequences of CR and LF characters.
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73       A script may look thus:
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75           #!/usr/bin/lgwam script
76           string
77           015F43BE4A17DAD915936B7A773154A80946AEC82EFBEECDA4A7D7B80806
78           hello
79           execute
80           foo=bar
81           magicword=xyzzy
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83       The first line starts with a hash mark so it is ignored.
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85       The  first  proper  line  (the second line) indicates the format of the
86       rest of the script. The 'string' format is the only format which is not
87       deprecated, so the first proper line always says 'string'.
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89       The  second  proper  line  contains  the  reference  of  a Logiweb page
90       expressed in mixed endian hexadecimal, c.f. REFERENCES below.
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92       The third proper line indicates the name of  the  program  ('hello'  in
93       this case).
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95       The  fourth  proper line indicates the aspect defining the program. The
96       lgc compiler always sets the aspect to 'execute'.
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98       All remaining lines define script options which are passed to the  pro‐
99       gram.
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101       When  lgwam  executes  a  Logiweb script, it first loads the referenced
102       page and all its transitively referenced pages. It does  so  using  the
103       LGW_PATH environment variable described under ENVIRONMENT below.
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105       Then  lgwam  looks  up the given aspect of the given name on the refer‐
106       enced page where both aspect and name are treated as strings. The  base
107       page  which comes with the distribution defines the 'execute' aspect of
108       'hello' such that the resulting program prints 'Hello World'.
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110       Then lgwam invokes the given aspect  of  the  given  name  in  the  way
111       described on the base page. See the base page for further information.
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ENVIRONMENT

114       Whenever  lgwam  needs  to  load  a page, it locates the page using the
115       LGW_PATH environment variable. If that variable is not set, it defaults
116       to
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118           $HOME/.logiweb/logiweb/:/rack.lgr
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120       The  value  of  LGW_PATH must be a list of locations separated by semi‐
121       colons. The default path above contains only one location and, thus, no
122       semicolons.
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124       To  load a referenced page, lgwam tries each location in turn. For each
125       location, lgwam replaces the rightmost colon character by the reference
126       of  the  page  expressed  in  mixed endian hexadecimal, c.f. REFERENCES
127       below. Then lgwam reads the file at the resulting  path,  if  any.  The
128       file must be a rack file, c.f. logiweb(5).
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REFERENCES

131       The  Logiweb  reference  of  a  Logiweb page is a sequence of around 30
132       bytes  which  identifies  the  page  uniquely.  References  are   often
133       expressed in mixed endian hexadecimal.
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135       In  mixed endian hexadecimal, each byte is represented by two hexadeci‐
136       mal digits with the most significant digit first. Bytes  are  given  in
137       network order. Capital letters are used for the hex digits A to F.
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AUTHOR

140       Klaus Grue, http://logiweb.eu/
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