diff options
| -rwxr-xr-x | corepkgs/buildenv/builder.pl.in | 2 | ||||
| -rw-r--r-- | doc/manual/package-management.xml | 34 | ||||
| -rw-r--r-- | src/libexpr/eval.cc | 28 | ||||
| -rw-r--r-- | src/libexpr/lexer.l | 1 | ||||
| -rw-r--r-- | src/libexpr/nixexpr.cc | 9 | ||||
| -rw-r--r-- | src/libexpr/parser.y | 12 | ||||
| -rw-r--r-- | src/libexpr/primops.cc | 2 |
7 files changed, 61 insertions, 27 deletions
diff --git a/corepkgs/buildenv/builder.pl.in b/corepkgs/buildenv/builder.pl.in index e53b383f19..d6dd2f4cf9 100755 --- a/corepkgs/buildenv/builder.pl.in +++ b/corepkgs/buildenv/builder.pl.in @@ -27,7 +27,7 @@ sub createLinks { $srcFile =~ /\/nix-support$/ || $srcFile =~ /\/log$/) { - # Do noting. + # Do nothing. } elsif (-d $srcFile) { diff --git a/doc/manual/package-management.xml b/doc/manual/package-management.xml index 470cb80a09..b717844b11 100644 --- a/doc/manual/package-management.xml +++ b/doc/manual/package-management.xml @@ -17,18 +17,12 @@ available for installation.</para> <para>In Nix, different users can have different <quote>views</quote> on the set of installed applications. That is, there might be lots of applications present on the system (possibly in many different -versions), but users can have a specific selection of those -active — where <quote>active</quote> just means that it appears -in a directory in the user's <envar>PATH</envar>.</para> - -<para>Such a view on the set of installed applications is called a -<emphasis>user environment</emphasis>, which is just a directory tree -consisting of symlinks to the files of the active applications. In -Nix, operations such as upgrading or removing components never -overwrite or remove the files of those components, and they don't even -touch the user environments that point to them. Rather, they cause a -<emphasis>new</emphasis> user environment to be constructed based on -the old one.</para> +versions), but users can have a specific selection of those active — +where <quote>active</quote> just means that it appears in a directory +in the user's <envar>PATH</envar>. Such a view on the set of +installed applications is called a <emphasis>user +environment</emphasis>, which is just a directory tree consisting of +symlinks to the files of the active applications. </para> <para>Components are installed from a set of <emphasis>Nix expressions</emphasis> that tell Nix how to build those components, @@ -168,7 +162,21 @@ set.</para></footnote></para> <sect1><title>Profiles</title> -<para>Bla</para> +<para>In Nix, operations such as upgrading or removing components +never overwrite or remove the files of those components, and they +don't even touch the user environments that point to them. Rather, +they cause a <emphasis>new</emphasis> user environment to be +constructed based on the old one. This is illustrated in Figure +bla.</para> + +<figure><title>User environments</title> + <mediaobject> + <imageobject> + <imagedata fileref='figures/userenv-frame3.png' format='PNG' /> + </imageobject> + </mediaobject> +</figure> + </sect1> diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc index 89cc8254d2..215692aeb3 100644 --- a/src/libexpr/eval.cc +++ b/src/libexpr/eval.cc @@ -230,7 +230,7 @@ Expr evalExpr2(EvalState & state, Expr e) try { return evalExpr(state, substArgs(e4, formals, e2)); } catch (Error & e) { - throw Error(format("while evaluating function at %1%:\n%2%") + throw Error(format("while evaluating the function at %1%:\n%2%") % showPos(pos) % e.msg()); } } @@ -241,7 +241,7 @@ Expr evalExpr2(EvalState & state, Expr e) subs.set(name, e2); return evalExpr(state, substitute(subs, e4)); } catch (Error & e) { - throw Error(format("while evaluating function at %1%:\n%2%") + throw Error(format("while evaluating the function at %1%:\n%2%") % showPos(pos) % e.msg()); } } @@ -258,7 +258,7 @@ Expr evalExpr2(EvalState & state, Expr e) try { return evalExpr(state, a); } catch (Error & e) { - throw Error(format("while evaluating attribute `%1%' at %2%:\n%3%") + throw Error(format("while evaluating the attribute `%1%' at %2%:\n%3%") % s1 % showPos(pos) % e.msg()); } } @@ -283,6 +283,26 @@ Expr evalExpr2(EvalState & state, Expr e) return evalExpr(state, e2); } + /* Withs. */ + if (atMatch(m, e) >> "With" >> e1 >> e2 >> pos) { + ATermMap attrs; + try { + e1 = evalExpr(state, e1); + queryAllAttrs(e1, attrs); + } catch (Error & e) { + throw Error(format("while evaluating the `with' definitions at %1%:\n%2%") + % showPos(pos) % e.msg()); + } + try { + e2 = substitute(attrs, e2); + checkVarDefs(state.primOps, e2); + return evalExpr(state, e2); + } catch (Error & e) { + throw Error(format("while evaluating the `with' body at %1%:\n%2%") + % showPos(pos) % e.msg()); + } + } + /* Generic equality. */ if (atMatch(m, e) >> "OpEq" >> e1 >> e2) return makeBool(evalExpr(state, e1) == evalExpr(state, e2)); @@ -357,7 +377,7 @@ Expr evalFile(EvalState & state, const Path & path) try { return evalExpr(state, e); } catch (Error & e) { - throw Error(format("while evaluating file `%1%':\n%2%") + throw Error(format("while evaluating the file `%1%':\n%2%") % path % e.msg()); } } diff --git a/src/libexpr/lexer.l b/src/libexpr/lexer.l index 9637fd304d..78d08d0725 100644 --- a/src/libexpr/lexer.l +++ b/src/libexpr/lexer.l @@ -48,6 +48,7 @@ if { return IF; } then { return THEN; } else { return ELSE; } assert { return ASSERT; } +with { return WITH; } let { return LET; } rec { return REC; } inherit { return INHERIT; } diff --git a/src/libexpr/nixexpr.cc b/src/libexpr/nixexpr.cc index dec734e466..78f89db5e5 100644 --- a/src/libexpr/nixexpr.cc +++ b/src/libexpr/nixexpr.cc @@ -296,7 +296,7 @@ void checkVarDefs(const ATermMap & defs, Expr e) ATMatcher m; ATerm name; ATermList formals; - ATerm body; + ATerm with, body; ATermList rbnds, nrbnds; if (atMatch(m, e) >> "Var" >> name) { @@ -340,6 +340,13 @@ void checkVarDefs(const ATermMap & defs, Expr e) } checkVarDefs(defs2, (ATerm) rbnds); } + + else if (atMatch(m, e) >> "With" >> with >> body) { + /* We can't check the body without evaluating the definitions + (which is an arbitrary expression), so we don't do that + here but only when actually evaluating the `with'. */ + checkVarDefs(defs, with); + } else if (ATgetType(e) == AT_APPL) { int arity = ATgetArity(ATgetAFun(e)); diff --git a/src/libexpr/parser.y b/src/libexpr/parser.y index 347516f692..88ee8326b8 100644 --- a/src/libexpr/parser.y +++ b/src/libexpr/parser.y @@ -41,11 +41,11 @@ ATerm makePos(YYLTYPE * loc, void * data) ATermList ts; } -%type <t> start expr expr_function expr_assert expr_if expr_op +%type <t> start expr expr_function expr_if expr_op %type <t> expr_app expr_select expr_simple bind inheritsrc formal %type <ts> binds ids expr_list formals %token <t> ID INT STR PATH URI -%token IF THEN ELSE ASSERT LET REC INHERIT EQ NEQ AND OR IMPL +%token IF THEN ELSE ASSERT WITH LET REC INHERIT EQ NEQ AND OR IMPL %nonassoc IMPL %left OR @@ -67,12 +67,10 @@ expr_function { $$ = ATmake("Function(<term>, <term>, <term>)", $2, $5, CUR_POS); } | ID ':' expr_function { $$ = ATmake("Function1(<term>, <term>, <term>)", $1, $3, CUR_POS); } - | expr_assert - ; - -expr_assert - : ASSERT expr ';' expr_assert + | ASSERT expr ';' expr_function { $$ = ATmake("Assert(<term>, <term>, <term>)", $2, $4, CUR_POS); } + | WITH expr ';' expr_function + { $$ = ATmake("With(<term>, <term>, <term>)", $2, $4, CUR_POS); } | expr_if ; diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc index 070ed1b54a..938d9bb8c1 100644 --- a/src/libexpr/primops.cc +++ b/src/libexpr/primops.cc @@ -205,7 +205,7 @@ static Expr primDerivation(EvalState & state, const ATermVector & _args) try { processBinding(state, value, ne, ss); } catch (Error & e) { - throw Error(format("while processing derivation attribute `%1%' at %2%:\n%3%") + throw Error(format("while processing the derivation attribute `%1%' at %2%:\n%3%") % key % showPos(pos) % e.msg()); } |